US20110252777A1 - Systems and methods for improving drivetrain efficiency for compressed gas energy storage - Google Patents
Systems and methods for improving drivetrain efficiency for compressed gas energy storage Download PDFInfo
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Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with accumulators
- F15B1/024—Installations or systems with accumulators used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/14—Energy-recuperation means
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
- H02P9/04—Control effected upon non-electric prime mover and dependent upon electric output value of the generator
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20507—Type of prime mover
- F15B2211/20515—Electric motor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/2053—Type of pump
- F15B2211/20569—Type of pump capable of working as pump and motor
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
- F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
- F15B2211/216—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being pneumatic-to-hydraulic converters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/63—Electronic controllers
- F15B2211/6303—Electronic controllers using input signals
- F15B2211/6306—Electronic controllers using input signals representing a pressure
- F15B2211/6309—Electronic controllers using input signals representing a pressure the pressure being a pressure source supply pressure
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/665—Methods of control using electronic components
- F15B2211/6655—Power control, e.g. combined pressure and flow rate control
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J15/00—Systems for storing electric energy
- H02J15/006—Systems for storing electric energy in the form of pneumatic energy, e.g. compressed air energy storage [CAES]
Definitions
- FIG. 22 depicts the hydraulic motor-pump 2110 , having one each of a high pressure and low pressure input/output 2130 and 2140 , with a series of pistons each driven using a computer controlled valve actuation scheme to allow for variable displacement operation at high efficiency.
- the major components include six radial piston assemblies 2110 a - f , each composed of a piston 2111 attached to an off-center rotating cam 2120 that turns a center axle 2121 .
- Each piston 2111 reciprocates in a housing 2112 that is allowed to pivot about a fixed end 2113 .
Abstract
Description
- This application claims priority to U.S. Provisional Patent Application Ser. Nos. 61/159,623, filed on Mar. 12, 2009; 61/227,591, filed on Jul. 22, 2009; and 61/229,853, filed on Jul. 30, 2009, the disclosures of which are hereby incorporated herein by reference in their entireties.
- This invention was made with government support under IIP-0810590 and IIP-0923633 awarded by the NSF. The government has certain rights in the invention.
- The invention relates to hydraulics and pneumatics, power generation, and control systems. More particularly, the invention relates the integration of variable and fixed displacement hydraulic motor-pumps in hydraulic-pneumatic energy storage and recovery systems and related control systems and methods to provide constant electrical power therefrom.
- Storing energy in the form of compressed gas has a long history and components tend to be well tested, reliable, and have long lifetimes. The general principles for compressed gas energy storage are generated energy (e.g., electric energy, etc.) is used to compress gas and thus converts the original energy to pressure potential energy; the energy is later recovered in a useful form (e.g. converted back to electric energy, etc.) via appropriate gas expansion. Advantages to compressed gas energy storage include low specific energy costs, long-lifetime, low maintenance, reasonable energy density, and good reliability. However, recovering the energy from the stored compressed gas has certain drawbacks. For example, systems that utilize pneumatic to hydraulic conversion to drive a hydraulic motor are subject to a decaying pressure profile, which in turn produces decreasing and/or irregular power output.
- Conventional usage of a fixed displacement (FD) hydraulic motor is to convert fluid power into rotational mechanical power. This is used, for example, in a hydraulically powered crane where a fluid power source is used to drive a FD hydraulic motor whose rotating shaft drives a winch that raises or lowers a load. Increasing or decreasing the pressure to the FD hydraulic motor increases or decreases the torque to the winch, allowing the load to be raised or lowered. In the afore-mentioned pneumatic to hydraulic conversion systems, especially those with accumulator discharge, the input to the hydraulic motor has a decaying pressure profile. For such a decaying pressure profile and for a FD hydraulic motor, in which torque is proportional to pressure, torque decreases proportionally. Likewise, hydraulic flow rate and motor RPM are typically proportional to pressure. With decaying pressure and torque and with the FD motor driving a constant load, RPM and flow rate also decay, which decreases power (torque times RPM) in a quadratic fashion.
- In addition, in a system in which a single fluid power source (usually at constant pressure) is used to power multiple FD hydraulic motors to drive multiple loads (e.g., to drive multiple winches with different loads), throttling valves are necessary to decrease the source pressure to a controlled pressure and provide torque control of each FD hydraulic motor, allowing each load to be independently controlled. The disadvantage with this approach is that a significant amount of energy is lost and converted to heat in the throttling valves, greatly reducing system efficiency.
- Variable displacement (VD) hydraulic motors were developed to provide torque control from a constant or nearly constant pressure fluid power source without the need for throttling valves. By eliminating the energy losses associated with throttling control valves, system efficiencies are greatly increased. To do this, the control system for the VD hydraulic motor increases or decreases the displacement of the motor to increase or decrease the torque output to account for changes in load.
- The prior art does not disclose systems and methods for providing constant electrical power with a staged hydraulic-pneumatic energy conversion system having hydraulic outputs having widely-varying pressures.
- The control systems and methods disclosed herein can be used in such applications as, for example, short-term power storage, long-term power storage, frequency regulation, and power quality control. The systems and methods allow a user to maintain electric output at constant power and frequency from a decaying, or otherwise widely-varying, pressure signal at the input to the hydraulic motor. For example, the systems and methods can be used with a fixed or variable displacement hydraulic motor in combination with a varying pressure profile, for example, such as a decaying pressure profile that results from a discharging accumulator. The control systems and methods disclosed herein are used with novel compressed air energy storage and recovery systems as described in U.S. patent application Ser. Nos. 12/421,057; 12/639,703; and 12/481,235; the disclosures of which are hereby incorporated by reference herein in their entireties, that include a hydraulic motor-pump which is driven by or used to pump hydraulic fluid over a range of pressures—from a mid-pressure to a high pressure (e.g. 300 psi to 3000 psi). The various systems include the use of staged hydraulic conversion and isothermal gas expansion and compression.
- Nearly constant power can be achieved by a FD hydraulic motor operating over a broad pressure range by varying RPM. With active control, as torque decreases with pressure, the FD hydraulic motor load can be reduced (e.g., by using power electronics) such that hydraulic flow rate and motor RPM increase, keeping a nearly constant power output (i.e., as pressure and torque decrease, RPM is increased proportionally, keeping power constant). Using a VD hydraulic motor with active control, as described herein, constant power can be achieved while also maintaining constant RPM and torque. By actively controlling the displacement as the pressure decays, the torque can be maintained as a constant. Likewise, RPM can be maintained as a constant through a feedback loop. Using the system to drive an electric generator, constant power can be achieved. By running the system with a synchronous generator with RPM fixed with line frequency and by performing VD system control based on torque feedback (or open-loop based on pressure measurements, or based on known pressure profiles), a constant RPM, constant torque, and thus constant power output can be achieved over a broad pressure range as described herein.
- For compressed gas systems, when the gas expands, the pressure will drop. When coupled with a hydraulic system, such as is the case with a hydraulic-pneumatic accumulator, hydraulic pressure similarly drops. In a hydraulic system where this pressure drops over the range of an expansion, when using a fixed displacement hydraulic motor with a constant load, as pressure drops, the torque and power drops. In many instances, it would be advantageous to minimize these changes in power level over the pressure range. For example, operating at a fixed electric power and frequency during system discharge would potentially allow an electric generator to be coupled to the grid without additional power conditioning equipment that would be required for a variable frequency, variable voltage, and/or variable power output.
- In pneumatic accumulator-discharge systems where an electric machine (motor-generator) is coupled directly to an FD hydraulic motor, if constant power is to be maintained, the RPM of the hydraulic motor and electric machine must be increased as accumulator pressure (and thus torque on the FD hydraulic motor shaft) decreases. Increased RPM can be achieved by modifying the load on the electric machine and thus on the hydraulic motor. If this is done, and if electric power output at grid frequency (e.g., 60 Hz) is to be produced by the system, then the electric output of the electric machine must be appropriately conditioned. A class of devices suitable for such load adjustment and power conditioning is the variable-frequency drive. As used herein, the term “variable frequency drive” (VFD) denotes an electronic device that is coupled to alternating-current line voltage on one side and to an electrical machine on the other, and through which power may flow in either direction. The frequency on the VFD's line side remains constant (e.g., 60 Hz) and the frequency on its machine side can vary. Such a device will be familiar to persons acquainted with the art of electrical machinery and power electronics.
- However, with active control, as described herein, as torque decreases the load on the FD hydraulic motor can be modified such that hydraulic flow rate and motor RPM increase, keeping power output constant: i.e., as torque decreases, RPM is increased proportionally, keeping power constant. One such system and method of control using power electronics is described herein. For example, one method for maintaining nearly constant power output over the range of pressures is to use an FD hydraulic motor to drive an electrical machine whose load is controlled by a VFD. Despite varying torque at the output of the hydraulic motor, RPM can be controlled in such a way so as to keep power nearly constant, while the VFD conditions the electric machine's electrical output to have a constant frequency (e.g., 60 Hz).
- Alternatively, a continuously variable transmission (CVT) can be placed between the shaft of the FD hydraulic motor and the shaft of the electrical machine. As used herein, the term “continuously variable transmission” denotes a mechanical device providing a connection between two rotating shafts, said connection having an effective gear ratio that can adjusted to any value within a certain range. The effective gear ratio of the CVT can be varied in such a way that as torque on the FD hydraulic motor shaft decays with accumulator discharge, constant RPM is maintained at the CVT's output (i.e., the shaft of the electric machine). In effect, the CVT adjusts the load on the hydraulic machine to keep mechanical power constant. Consequently, constant-power, constant-frequency electricity are produced by the electric machine. One such system and method of control using a mechanical transmission is described herein.
- Generally, the foregoing systems and methods for providing constant power can be used to control one or more parameters of the VFD, such as the load presented to the electric machine, and include monitoring at least one operational parameter of the FD hydraulic motor (e.g., torque on hydraulic motor shaft, torque on shaft of electric generator coupled to the hydraulic motor, output voltage of electric generator coupled to the hydraulic motor) and operating the VFD to vary the load seen by the electric machine. The operational parameter or parameters can also be used to control the effective gear ratio of the CVT so as to vary the load seen by the hydraulic motor.
- Additionally, the control system can be used to vary electrical load on the generator. That is, the control system may be configured to increase the RPM of an electric generator by controlling a VFD in such a way as to modify the generator's load in response to decreasing torque on its shaft. Constant power output from the electric generator is thereby maintained and the output voltage of the electric generator can be synchronized to a power grid. Additionally, or alternatively, the control system can be used to vary the mechanical load on the hydraulic motor. The control system may be configured to increase the RPM of the hydraulic motor by adjusting the CVT in such a way as to decrease the hydraulic motor's load in response to decreasing torque on its shaft. Motor RPM consequently increases, constant power output from the electric generator is maintained, and the output voltage of the electric generator can be synchronized to a power grid.
- Other systems and methods for providing constant power, improving efficiency, and overcoming the limitations of fixed displacement motors when operating over a wide pressure range include using active control with a VD hydraulic motor. For example, efficiency for an electric motor-generator can vary substantially based on torque and RPM; when the hydraulic motor-pump in the staged hydraulic conversion system is attached to an electric motor-generator, it would be advantageous to operate at a narrow range or fixed value for RPM (e.g. 1800 RPM) and torque to operate at peak efficiency, increasing electric motor, and thus system, efficiency. Likewise, operating at a fixed RPM and power (and thus constant voltage, frequency, and current for an electric generator) during system discharge would allow an electric generator to be synchronized with the grid and potentially eliminate additional power conditioning equipment that would be required for a variable frequency, variable voltage, and/or variable power output. By using the VD hydraulic motor-pump in lieu of the FD hydraulic motor, the displacement per revolution can be controlled in such a way as to maintain a nearly constant torque and proportionally increasing flow rate such that the RPM and power output are kept nearly constant. For the novel compressed air energy storage and recovery system using staged hydraulic conversion described in the above-referenced applications, this constant RPM and power allows for a reduction in electric system costs by potentially eliminating power conditioning equipment necessary for a variable frequency, voltage, or power output, while at the same time improving overall system efficiency by operating at the peak efficiency region of the electric generator; likewise, the increasing flow rate maintains a nearly constant power throughout a decreasing pressure range, also adding value to the energy storage and recovery system.
- Furthermore, high efficiency standard commercial variable displacement motor-pump designs include radial piston style (external cam), which are used primarily at low speeds, and axial piston styles (swash-plate, bent-axis). For axial piston motors, the piston assembly typically rotates in an oil bath; for large displacement axial piston motors, viscous drag (which is proportional to speed squared) limits efficiency at high rotational speeds. Additionally, for the radial and axial piston styles displacement is reduced by reducing piston stroke; as piston stroke drops below half the total possible stroke, efficiency typically drops substantially. As described herein, newly developed VD hydraulic motor-pumps which use digital control to open and close valves to control displacement are able to achieve substantially higher efficiencies at large displacement sizes (no longer rotating the entire piston assembly in an oil bath) and maintain high efficiency at low relative displacements (by not changing piston stroke length). In these digitally controlled pumps/motors, relative displacement is controlled by actively opening and closing valves to each piston, such that each piston may or may not be exposed to high pressure each time the rotating cam completes a revolution. Unlike the standard commercial VD motor-pumps, the piston always completes a full stroke, maintaining high motor-pump efficiency even at low relative displacements.
- In one aspect, the invention relates to a system for providing a constant electrical output from a compressed gas energy storage and recovery system. The system includes a hydraulic-pneumatic energy storage and recovery system configured to provide a varying pressure profile at, at least one outlet, a variable displacement hydraulic motor-pump in fluid communication with the at least one outlet, and a control system in communication with the variable displacement hydraulic motor-pump. The control system controls at least one variable, such as pressure, piston position, power, flow rate, torque, RPM, current, voltage, frequency, and displacement per revolution. The use of the variable displacement hydraulic motor and associated control system allow a user to achieve near constant expansion and compression power in the hydraulic-pneumatic energy storage and recovery system, while maintaining near constant RPM or torque at the shaft of an electric motor-generator.
- In various embodiments, the system also includes an electric motor-generator mechanically coupled to the variable displacement hydraulic motor-pump. The variable displacement hydraulic motor-pump converts hydraulic work to mechanical energy to drive a drive shaft of the electric motor-generator, and the electric motor generator converts the mechanical energy to electrical energy. The system may further include power electronics in communication with the electric motor-generator to synchronize an output (e.g., voltage, current, power, frequency) of the electric motor-generator to a power supply. In one embodiment, the control system is configured to vary the displacement per revolution of the variable displacement hydraulic motor-pump in response to the varying pressure profile at the at least one outlet. The control system can vary flow rate inversely with pressure as a function of time. For example, during an expansion cycle (energy recovery), the control system increases the displacement per revolution of the variable displacement hydraulic motor as the pressure profile decays. During a compression cycle (energy storage), the control system decreases the displacement per revolution as the pressure profile increases, which reduces fluctuations in the energy drawn from the power supply during an energy storage cycle. In another embodiment, the control system is configured to maintain a constant torque or RPM of the variable displacement hydraulic motor-pump to maintain an output (e.g., voltage) by the electric motor-generator. The output can include an output produced at either the shaft side of the electric motor-generator (e.g., torque) or the electric side of the motor-generator (e.g., voltage). The control system controls the variable displacement hydraulic motor-pump to maintain an output at the electric motor-generator that matches a required input for a power supply.
- In additional embodiments, the system includes a graphical display in communication with the variable displacement hydraulic motor-pump, which can display one or more parameters, such as piston position, power, pressure, flow rate, torque, RPM, current, and voltage versus time. The hydraulic-pneumatic energy storage and recovery system can use staged hydraulic conversion to provide the varying pressure profile and include a cylinder assembly including a staged pneumatic side and a hydraulic side, the sides being separated by a movable mechanical boundary mechanism that transfers energy therebetween, and a compressed gas storage system in fluid communication with the cylinder assembly. The hydraulic-pneumatic storage and recovery system can include any of the components and their associated configurations as disclosed in the incorporated patent applications. The hydraulic-pneumatic storage and recovery system can also include a heat transfer subsystem to provide isothermal expansion and compression of the gas.
- In another aspect, the invention relates to a system for providing a constant electrical output from a compressed gas energy storage and recovery system. The system includes a hydraulic-pneumatic energy storage and recovery system configured to provide a varying pressure profile at, at least one outlet, a fixed displacement hydraulic motor-pump in fluid communication with the at least one outlet, an electric motor-generator mechanically coupled to the fixed displacement hydraulic motor-pump, and a control system. The control system is in communication with a control device to control at least one variable, such as power, flow rate, torque, RPM, current, voltage, and frequency.
- In various embodiments, the control system is configured to maintain a constant torque or RPM of the fixed displacement hydraulic motor-pump to maintain a constant output (e.g., voltage, current, power, frequency) by the electric motor-generator. The control system is also configured to vary a flow rate of the fixed displacement hydraulic motor-pump in response to the varying pressure profile at the at least one outlet. For example, increasing the flow rate in response to a decaying pressure profile during an expansion cycle or decreasing the flow rate in response to an increasing pressure profile during a compression cycle. In one embodiment, the control device includes a variable frequency drive coupled to the electric motor-generator to control a load on the hydraulic motor-pump. In another embodiment, the control device includes a continuously variable transmission disposed between the hydraulic motor-pump and the electric motor-generator to control a load on the hydraulic motor-pump. Additionally, the control device can include power electronics in communication with the electric motor-generator to synchronize an output of the electric motor-generator to a power supply.
- The hydraulic-pneumatic energy storage and recovery system can use staged hydraulic conversion to provide the varying pressure profile and include a cylinder assembly including a staged pneumatic side and a hydraulic side, the sides being separated by a movable mechanical boundary mechanism that transfers energy therebetween, and a compressed gas storage system in fluid communication with the cylinder assembly. The hydraulic-pneumatic storage and recovery system can include any of the components and their associated configurations as disclosed in the incorporated patent applications. The hydraulic-pneumatic storage and recovery system can also include a heat transfer subsystem to provide isothermal expansion and compression of the gas.
- In another aspect, the invention relates to a system for providing a constant electrical output from a compressed gas energy storage and recovery system. The system can include a hydraulic-pneumatic energy storage and recovery system configured to provide a varying pressure profile at, at least one outlet, a digital displacement hydraulic motor-pump in fluid communication with the at least one outlet, and a control system in communication with the digital displacement hydraulic motor-pump. The control system controls at least one variable, such as pressure, piston position, power, flow rate, torque, RPM, current, voltage, frequency, and displacement per revolution. As used herein, a digital-displacement hydraulic motor-pump is a hydraulic motor-pump that varies its effective displacement by actively changing the number of pistons powered during each rotation (e.g., via valving), with all powered piston providing a full stroke, as compared to a conventional hydraulic motor-pump in which every piston is powered each rotation, but the length of the stroke is changed to change displacement.
- In various embodiments, the system also includes an electric motor-generator mechanically coupled to the digital displacement hydraulic motor-pump. The hydraulic motor-pump converts hydraulic work to mechanical energy to drive a drive shaft of the electric motor-generator, and the electric motor generator converts the mechanical energy to electrical energy. The system can also include power electronics in communication with the electric motor-generator to synchronize an output (e.g., current, voltage, power, frequency) of the electric motor-generator to a power supply. Additionally, the control system can be configured to vary the displacement per revolution of the digital displacement hydraulic motor-pump in response to the varying pressure profile at the at least one outlet; for example, increasing the flow rate in response to a decaying pressure profile during an expansion cycle or decreasing the flow rate in response to an increasing pressure profile during a compression cycle. In one embodiment, the control system is configured to maintain a constant torque or RPM of the digital displacement hydraulic motor-pump to maintain an output by the electric motor-generator. The control system can control the digital displacement hydraulic motor-pump to maintain an output at the electric motor-generator that matches a required input for a power supply.
- In one embodiment, the digital displacement hydraulic motor-pump includes a high pressure input-output, a low pressure input-output, an off-center rotating cam, a plurality of radial piston assemblies coupled to the off-center rotating cam, and a control valve arrangement responsive to the control system for operating the hydraulic motor-pump at, at least one of a substantially constant pressure, power output, flow rate, torque, RPM, or displacement per revolution. In one embodiment, the control valve arrangement includes pairs of high speed valves in fluid communication with each piston assembly and the control system actuates the high speed valves to control aggregate displacement of the hydraulic motor-pump. In one embodiment, the digital displacement hydraulic motor-pump can include a plurality of high-pressure inputs-outputs and a plurality of low-pressure inputs-outputs.
- Furthermore, the hydraulic-pneumatic energy storage and recovery system can use staged hydraulic conversion to provide the varying pressure profile and include a cylinder assembly including a staged pneumatic side and a hydraulic side, the sides being separated by a movable mechanical boundary mechanism that transfers energy therebetween, and a compressed gas storage system in fluid communication with the cylinder assembly. The hydraulic-pneumatic storage and recovery system can include any of the components and their associated configurations as disclosed in the incorporated patent applications. The hydraulic-pneumatic storage and recovery system can also include a heat transfer subsystem to provide isothermal expansion and compression of the gas.
- In another aspect, the invention relates to a method of providing a constant output from a compressed gas energy storage and recovery system. The method includes the steps of providing a hydraulic-pneumatic energy storage and recovery system configured to provide a varying pressure profile at, at least one outlet, providing a variable displacement hydraulic motor-pump in fluid communication with the at least one pressure outlet, providing an electric motor-generator mechanically coupled to the variable displacement hydraulic motor-pump, monitoring a pressure of the at least one hydraulic outlet, monitoring at least one operational parameter of at least one of the variable displacement hydraulic motor-pump or the electric motor-generator, and operating a control system to vary an operational parameter of at least one of the variable displacement hydraulic motor-pump or the electric motor-generator to maintain at least one output parameter of the system constant. The variable displacement hydraulic motor-pump converts hydraulic work to mechanical energy to drive a drive shaft of the electric motor-generator, and the electric motor generator converts the mechanical energy an electrical output.
- In various embodiments, the at least one constant output parameter can be a torque, RPM, power, voltage, current, and/or frequency. The operational parameter of the hydraulic motor-pump can be pressure, piston position, power, flow rate, torque, RPM, and/or displacement per revolution. The operational parameter of the electric motor-generator can be power, torque, RPM, current, voltage, and/or frequency.
- In one embodiment, the step of operating the control system includes varying a displacement per revolution of the variable displacement hydraulic motor-pump to maintain the at least one output parameter constant, as described above to compensate for a decaying pressure profile during expansion or an increasing pressure profile during compression. For example, the control system can be configured to increase the flow rate of the variable displacement hydraulic motor-pump in response to a decreasing pressure at the at least one outlet. Additionally, the step of operating the control system can include maintaining at least one of constant torque or RPM of the variable displacement hydraulic motor-pump to maintain a constant output at the electric motor-generator. The step of operating the control system can also include synchronizing an output (e.g., voltage) of the electric motor-generator with a power grid.
- These and other objects, along with the advantages and features of the present invention herein disclosed, will become apparent through reference to the following description, the accompanying drawings, and the claims. Furthermore, it is to be understood that the features of the various embodiments described herein are not mutually exclusive and can exist in various combinations and permutations.
- In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the invention. In the following description, various embodiments of the present invention are described with reference to the following drawings, in which:
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FIG. 1 is a schematic diagram of an open-air hydraulic-pneumatic energy storage and recovery system using a hydraulic motor for generating electrical power in accordance with one embodiment of the invention; -
FIG. 2 is a schematic diagram of the major components related to a system and method for providing a constant output from a compressed gas energy storage and recovery system using a fixed displacement hydraulic motor-pump; -
FIGS. 3A-3E are graphical representations of the hydraulic pressure, motor torque, hydraulic flow rate, shaft RPM, and generator output power for a single pressure profile for a representative pressure range produced by the system ofFIG. 2 ; -
FIGS. 4A-4E are graphical representations of the hydraulic pressure, shaft torque, hydraulic flow rate, hydraulic motor RPM, and motor output power for a series of pressure profiles for an exemplary cyclic operation of the system ofFIG. 2 ; -
FIG. 5 is a schematic diagram of the major components related to a system and method for providing a constant output from a compressed gas energy storage and recovery system using a fixed displacement hydraulic motor-pump and a continuously variable transmission; -
FIGS. 6A-6H are graphical representations of the hydraulic pressure, hydraulic motor torque, hydraulic flow rate, hydraulic motor shaft RPM, generator output power, CVT gear ratio, generator shaft RPM, and generator torque for a single pressure profile for a representative pressure range produced by the system ofFIG. 5 ; -
FIGS. 7A-7H are graphical representations of the hydraulic pressure, hydraulic motor torque, hydraulic flow rate, hydraulic motor shaft RPM, generator output power, CVT gear ratio, generator shaft RPM, and generator torque for a series of pressure profiles for an exemplary cyclic operation of the system ofFIG. 5 ; -
FIG. 8 is a schematic diagram of the major components related to conversion efficiency for a compressed air energy storage and recovery system using staged hydraulic conversion; -
FIG. 9 is a schematic diagram of the major components related to conversion efficiency for a compressed air energy storage and recovery system using staged hydraulic conversion, where a fixed displacement hydraulic motor-pump is used, including graphic representations of the various operational parameters, such as piston profile, power, pressure, flow, torque, RPM, current and voltage versus time for various stages or operation; -
FIG. 10 is a schematic diagram of the major components related to conversion efficiency for a compressed air energy storage and recovery system using staged hydraulic conversion, where a variable displacement hydraulic motor-pump and non-optimized control scheme is used, including graphic representations of the various operational parameters, such as piston position, power, pressure, flow, torque, RPM, current and voltage versus time for the various stages; -
FIG. 11 is a schematic of the components related to conversion efficiency for compressed air energy storage using staged hydraulic conversion, where a variable displacement hydraulic motor-pump and optimal control scheme is used for providing constant power, and graphic representations of the various operational parameters, such as piston position, power, pressure, flow, torque, RPM, current and voltage versus time for the various stages; -
FIG. 12 is a schematic representation of the major components related to one embodiment of a system and method for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile and using a variable displacement hydraulic motor; -
FIG. 13 is a schematic representation of the major components related to another embodiment of a system and method for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile and using a variable displacement hydraulic motor; -
FIGS. 14A-14C are graphical representations of the hydraulic pressure, flow rate, and motor output power for a single pressure profile for a representative pressure range related to the systems and methods ofFIGS. 12 and 13 ; -
FIGS. 15A-15E are graphical representations of the hydraulic pressure, motor displacement, motor RPM, motor torque, and motor output power for a series of pressure profiles for an example cyclic operation of the systems and methods ofFIGS. 12 and 13 ; -
FIG. 16 is a schematic representation of the major components related to another embodiment of a system and method for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile and using a variable displacement hydraulic motor; -
FIG. 17A is a schematic representation of a hydraulic drivetrain including a single fluid power source and a single fluid power consumer, wherein the fluid power consumer is a fixed displacement hydraulic motor; -
FIG. 17B is an equation describing the torque, pressure, and displacement relationship for the hydraulic motor inFIG. 17A ; -
FIG. 18A is a schematic representation of a hydraulic drivetrain including a single fluid power source and multiple fluid power consumers, wherein the fluid power consumers are fixed displacement hydraulic motors; -
FIG. 18B is a set of equations describing the torque, pressure, and displacement relationships for the hydraulic motors inFIG. 18A ; -
FIG. 19A is a schematic representation of a hydraulic drivetrain including a single fluid power source and multiple fluid power consumers wherein the fluid power consumers are variable displacement hydraulic motors; -
FIG. 19B is a set of equations describing the torque, pressure, and displacement relationships for the hydraulic motors inFIG. 19B ; -
FIG. 20A is a schematic representation of a hydraulic drivetrain including a single fluid power source and a single fluid power consumer, wherein the fluid power source is a non-controlled, non-constant pressure source and the fluid power consumer is a variable displacement motor producing a constant output speed; -
FIG. 20B is an equation describing the torque, pressure, and displacement relationship for the hydraulic motor inFIG. 20A ; -
FIG. 21 is a schematic representation of the major components for an alternative system and method for improving drivetrain efficiency for a compressed gas energy storage and recovery system using staged hydraulic conversion; -
FIG. 22 is a schematic representation of one embodiment of a high-efficiency, variable volume hydraulic motor-pump for use in the system and method ofFIG. 21 ; -
FIG. 23 is a schematic representation of the major components for an alternative system and method for improving drivetrain efficiency for a compressed gas energy storage and recovery system using staged hydraulic conversion; and -
FIG. 24 is a schematic representation of one embodiment of a high-efficiency, variable volume hydraulic motor-pump for use in the system and method ofFIG. 23 . -
FIG. 1 depicts generally a basic hydraulic-pneumaticenergy conversion system 1 that stores and recovers electrical energy using at least one hydraulic motor. Various hydraulic-pneumatic energy conversion systems are described in detail in the above incorporated patent applications. Thesystem 1 includes one or more high-pressure gas/air storage tanks tank 2 is joined in parallel via a manual valve(s) 4 a, 4 b, . . . 4 n, respectively, to amain air line 8. Thevalves 4 are not limited to manual operation, as the valves can be electrically, hydraulically, or pneumatically actuated, as can all of the valves described herein. Thetanks 2 are each provided with apressure sensor temperature sensor control system 20 via appropriate wired and wireless connections/communications. Additionally, the sensors 12, 14 could include visual indicators. - The
control system 20 can be any acceptable control device with a human-machine interface. For example, thecontrol system 20 could include a computer (for example a PC-type) that executes a stored control application in the form of a computer-readable software medium. The control application receives telemetry from the various sensors to be described below, and provides appropriate feedback to control valve actuators, motors, and other needed electromechanical/electronic devices. - The
system 1 further includespneumatic valves main air line 8 with anaccumulator 16 and anintensifier 18. As previously stated, thesystem 1 can include any number and combination ofaccumulators 16 andintensifiers 18 to suit a particular application. Thepneumatic valves 6 are also connected to avent 10 for exhausting air/gas from theaccumulator 16, theintensifier 18, and/or themain air line 8. - The
system 1 further includeshydraulic valves accumulator 16 and theintensifier 18 with a hydraulic motor-pump 30. The specific number, type, and arrangement of the hydraulic valves 28 and thepneumatic valves 6 are collectively referred to as the control valve arrangements. In addition, the valves are generally depicted as simple two way valves (i.e., shut-off valves); however, the valves could essentially be any configuration as needed to control the flow of air and/or fluid in a particular manner. The hydraulic line between theaccumulator 16 andvalves intensifier 18 andvalves sensors 26 that relay information to thecontrol system 20. - The motor-
pump 30 can be a fixed or variable displacement piston-type assembly having a shaft 31 (or other mechanical coupling) that drives, and is driven by, a combination electrical motor andgenerator assembly 32. The motor-pump 30 could also be, for example, an impeller, vane, or gear type assembly. The motor-generator assembly 32 is interconnected with a power distribution system and can be monitored for status and output/input level by thecontrol system 20. - The
system 1 can also include heat transfer subsystems in fluid communication with the air chambers of the accumulators and intensifiers and the high pressure storage tanks that provide improved isothermal expansion and compression of the gas. Various heat transfer subsystems are described in detail in the above incorporated patent applications. -
FIG. 2 depicts the major components related to a system and method for providing constant power from a hydraulic-pneumatic energy storage and recovery system using staged hydraulic conversion that provides a widely-varying pressure profile to a FD hydraulic motor-pump by using a closed loop control system and a variable frequency drive (VFD) to adjust the load seen by the electric generator and to produce constant electric power at a constant frequency. - The major regions illustrated in
FIG. 2 include a source of pressurizedhydraulic fluid 101, such as a hydraulic-pneumatic accumulator or system as described above with respect toFIG. 1 , which is driving the FD hydraulic motor-pump 110 providing rotary motion (as indicated by arrow 121) of anoutput shaft 120. - The output shaft drives an electric motor-
generator 130 havingelectric output 131. Thiselectric output 131 is the input of theVFD 140 having anelectric output 141. In this illustration, the outlet of thehydraulic motor 110 is at low pressure and is directed to ahydraulic fluid reservoir 102; however, the outlet could be directed back to the source of pressurizedhydraulic fluid 101, as shown inFIG. 1 . Atorque sensor 150 on theshaft 120 provides information via achannel 151 to theVFD 140, which adjusts the load seen by the generator accordingly. Theoutput 141 of theVFD 140 is a sinusoidal voltage having a constant frequency (e.g., 60 Hz) and constant power. -
FIGS. 3A-3E are graphical representations of the hydraulic pressure (A), motor torque (B), hydraulic flow rate (C), shaft RPM (D), and generator output power (E) for a single pressure profile for a representative pressure range delivered to the FD hydraulic motor-pump using the system and method of the invention for providing constant power from the widely-varying pressure profile. As shown inFIG. 3A , a pressure profile is depicted for a simulated system using a hydraulic pneumatic accumulator with an initial pressure of 3000 psi. As the compressed gas expands in the accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. Torque on the output shaft of the hydraulic motor decreases in proportion to the pressure (FIG. 3B ), which in all examplary figures is shown as a 25 cc/rev hydraulic motor. The load on the generator (and, consequently, the mechanical load on the FD hydraulic motor shaft) is decreased by the VFD in proportion to the sensed torque in such a way that flow rate through the FD motor increases as shown inFIG. 3C . Shaft RPM, identical for both the hydraulic and electric machines, increases proportionately as shown inFIG. 3D . In this way, the power output of both the hydraulic motor (which is identical to the output of the electric generator and VFD, assuming zero losses for schematic purposes) is kept nearly constant as a function of time, as shown inFIG. 3E . The output frequency of the electric generator increases in proportion to shaft RPM, but the output frequency of the VFD is constant. -
FIGS. 4A-4E are graphical representations of the hydraulic pressure (A), shaft torque (B), hydraulic flow rate (C), hydraulic motor RPM (D), and motor output power (E) for a series of pressure profiles during a cyclic operation of the system ofFIG. 2 . InFIG. 4A , a set of three cyclical pressure profiles are shown for a simulated process where successive hydraulic pneumatic accumulators are discharged with an initial pressure of 3000 psi. As the compressed gas expands in each successive accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. As shown inFIG. 4B , for a FD motor, torque decreases with decreasing pressure. The load on the generator (and, consequently, the mechanical load on the FD hydraulic motor shaft) is decreased by the VFD in proportion to the sensed torque in such a way that flow rate through the FD motor increases as shown inFIG. 4C . Shaft RPM, identical for both the hydraulic and electric machines, increases proportionately as shown inFIG. 4D . In this way, power is kept nearly constant as a function of time as shown inFIG. 4E . -
FIG. 5 depicts the major components related to an alternative system and method for providing a constant output (e.g., power, current, voltage, frequency) from a hydraulic-pneumatic energy storage and recovery system using staged hydraulic conversion that provides a widely-varying pressure profile to a FD hydraulic motor-pump by using a closed loop control system and a continuously variable transmission (CVT). The systems and methods of the invention are capable of maintaining constant RPM for the electric generator and so produce constant electric power at a constant frequency. - The major regions illustrated in
FIG. 5 include the source of pressurizedhydraulic fluid 101, as discussed above, which is driving the FDhydraulic motor 110, providing rotary motion (as indicated by arrow 121) of theoutput shaft 120. Theoutput shaft 120 drives theCVT 160 whoseoutput shaft 165 drives the electric motor-generator 130 havingelectric output 131. Atorque sensor 150 on theshaft 120 of the FDhydraulic motor 110 communicates information by achannel 151 to a control unit (e.g., a computer) 170. This control unit controls the effective gear ratio of the CVT through a mechanical linkage (or combination of information channel and mechanical linkage) 175. The effective gear ratio of the CVT is adjusted in such a way as to provide constant RPM and torque to theshaft 165 of theelectric generator 130. In this illustration, the outlet of thehydraulic motor 110 is at low pressure and is directed to ahydraulic fluid reservoir 102, but as discussed above could be directed back to the source of pressurizedhydraulic fluid 101. Theoutput 131 of theelectric generator 130 is a sinusoidal voltage having a constant frequency (e.g., 60 Hz) and constant power. -
FIGS. 6A-6H are graphical representations of the hydraulic pressure (A), hydraulic motor torque (B), hydraulic flow rate (C), hydraulic motor shaft RPM (D), generator output power (E), CVT gear ratio (F), generator RPM (G), and generator torque (H) for a single pressure profile for a representative pressure range delivered to the fixed hydraulic motor-pump using the system and method of the invention for providing constant power from the widely-varying pressure profile. As shown inFIG. 6A , a pressure profile is depicted for a simulated system using a hydraulic pneumatic accumulator with an initial pressure of 3000 psi. As the compressed gas expands in the accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. Torque on the output shaft of the hydraulic motor decreases in proportion to the pressure (FIG. 6B ). The effective gear ratio of the CVT is adjusted in proportion to torque in such a way that load on the FD hydraulic motor shaft is decreased and the flow rate through the FD motor increases as shown inFIG. 6C . Shaft RPM of the FD hydraulic motor increases proportionately, as shown inFIG. 6D . In this way, the power output of the hydraulic motor is kept nearly constant as a function of time, as shown inFIG. 6E . Shaft RPM (FIG. 6G ) and torque (FIG. 6H ) on the other side of the CVT, i.e., at the input of the electric generator, remains constant by continuously varying the gear ratio as shown inFIG. 6F . In this way, the output frequency, voltage, current, and power of the electric generator remains nearly constant. -
FIGS. 7A-7H are graphical representations of the hydraulic pressure (A), hydraulic flow rate (B), motor RPM (C), hydraulic motor shaft RPM (D), generator output power (E), CVT gear ratio (F), generator RPM (G), and generator torque (H) for a series of pressure profiles generated during a cyclic operation of the system ofFIG. 5 . InFIG. 7A , a set of three cyclical pressure profiles are shown for the simulated process where successive hydraulic pneumatic accumulators are discharged with an initial pressure of 3000 psi. As the compressed gas expands in each successive accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. Torque on the output shaft of the hydraulic motor decreases in proportion to the pressure (FIG. 7B ). The effective gear ratio of the CVT is adjusted in proportion to torque in such a way that load on the FD hydraulic motor shaft is decreased and the flow rate through the FD motor increases as shown inFIG. 7C . Shaft RPM of the FD hydraulic motor increases proportionately as shown inFIG. 7D . In this way, the power output of both the hydraulic motor and electric generator is kept nearly constant as a function of time, as shown inFIG. 7E . Shaft RPM (FIG. 7G ) and torque (FIG. 7H ) on the other side of the CVT, i.e. at the input of the electric generator, remains constant by continuously varying the gear ratio as shown inFIG. 7F . In this way, the output frequency, voltage, current, and power of the electric generator are kept nearly constant as a function of time. -
FIG. 8 depicts generally the major components for improving conversion efficiency of compressed air energy storage using staged hydraulic conversion and the four major energy conversion stages. The major regions illustrated inFIG. 8 include compressedgas energy 201, which is converted tohydraulic energy 202 via a pneumatic to hydraulic device, such as anaccumulator 210 orintensifier 220, with the pneumatic to hydraulic pressure ratio determined by relative piston sizing and selected based on pressure levels and actuation ofvalves 270 as, for example, described in the above-incorporated patent applications. The dashed line separatingcompressed gas energy 201 andhydraulic energy 202 represents a transition between energy types and thus has an associated efficiency—compressed gas potential energy to work done by the hydraulic fluid. Optimization of this efficiency, in part through the use of near isothermal expansion and compression, is also discussed in the above incorporated patent applications. - The pressurized hydraulic fluid in
region 202 is driven by or used to drive a hydraulic motor-pump 230, converting the work performed by or on the fluid to or frommechanical energy 203 typically in the form of a rotating drive shaft. This transition, indicated by the dashed line separatinghydraulic energy 202 andmechanical energy 203, represents the hydraulic to mechanical conversion efficiency and is dependent in part on the efficiency characteristics of the hydraulic motor-pump 230, which vary with pressure/torque and flow/RPM. In practice, this drive shaft will be connected to an electric motor-generator 240, which converts themechanical energy 203 toelectrical energy 204. This transition, indicated by the dashed line separatingmechanical energy 203 andelectrical energy 204, represents the mechanical to electrical conversion efficiency and is dependent in part on the efficiency characteristics of the electric motor-generator 240, which vary with torque and RPM. - Typically, this electrical motor-
generator 240 will be further connected topower electronics 250 to condition the electrical motor-generator 240 input/output power to the power supply 260 (e.g., an electrical power grid). The effect of the addition ofpower electronics 250 here is included in overall mechanical to final electrical efficiency. As proposed inFIGS. 10 and 11 , direct operation of the electric motor-generator 250 from thepower supply 260 can improve overall efficiency by removing any inefficiency from the addition ofpower electronics 250. -
FIG. 9 depicts generally the major components related to conversion efficiency for compressed air energy storage using staged hydraulic conversion, where a FD hydraulic motor-pump 230 is used.FIG. 9 illustrates the four major energy conversion stages discussed above (compressedgas energy 201,hydraulic energy 202,mechanical energy 203, and electrical energy 204). In addition,FIG. 9 graphically depicts the various operational parameters of the system, such as piston position, power, pressure, flow, torque, RPM, current and voltage versus time for those stages. It should be noted that for simplicity of description, the case of expansion (compressed air energy storage and recovery system discharge) is displayed and described for the graphs inFIG. 9 , but the case of compression (system charging) can be imagined by reversing the time axis on the various plots. - Starting in
compressed gas energy 201 region, a set amount of compressed gas is admitted and then expanded in a pneumatic hydraulic device such as theaccumulator 210 driving hydraulic fluid through hydraulic motor-pump 230. The hydraulic fluid pressure (directly related to compressed gas pressure) falls as a function of time as indicated in the first half ofgraph 320. For all graphs, two expansions are shown for the time scale. At the mid-point in time, a second pneumatic hydraulic device such as theintensifier 220 admits and expands a fixed amount of compressed gas. For a FDhydraulic motor 230, the flow rate will tend to drop with pressure as indicated ingraph 321, with a fixed load. Piston speed in theaccumulator 210 changes with flow rate, and thus piston position is related in an integral fashion to flow rate as indicated ingraph 310. As hydraulic power is pressure times flow rate, power drops as a function of time as the product ofgraph 320 andgraph 321 as indicated ingraph 322. For FDhydraulic motor 230, output torque is related to pressure,graph 320, as indicated ingraph 330, and hydraulic motor output RPM is related to flowgraph 321 as indicated ingraph 331. Similarly, converting mechanical 203 to electrical 204 power, motor-generator 240 current is related totorque graph 330 as indicated ingraph 340, and thus also tracks with pressure. Electric motor-generator 240 voltage is related toRPM graph 331 as indicated ingraph 341. Power in each stage: compressedgas energy 201,hydraulic energy 202,mechanical energy 203, andelectrical energy 204, are closely related, scaled by efficiencies of conversions, and fall with time. -
Power electronics 250 can be used to transform voltage to a constant value as a function of time for a final power supply 260 (e.g. for use on the power grid), as indicated ingraph 351. Additionally, short-term energy storage devices such as ultracapacitors can be used with the power electronics to smooth current,graph 350, and power supply,graph 352, as a function of time. This addition of power electronics and potentially short-term energy storage adds cost and complexity to the energy storage and recovery system, while adding additional electric conversion losses, potentially decreasing overall system efficiency. Additionally, efficiency of both the FD hydraulic motor-pump 230 and electric motor-generator 240 are dependent on operating torque and RPM, and thus when varied over a large range as indicated ingraph 330 andgraph 331 both may suffer lower efficiencies over the course of a full expansion than if operated over a narrow or fixed range of torque and RPM. As discussed with respect toFIGS. 2-7 , near constant torque and RPM can be achieved by using a VFD or CVT. However, it is also possible to achieve constant power output by using a VD hydraulic motor-pump as discussed with respect toFIG. 11 . -
FIG. 10 depicts generally the major components related to conversion efficiency for compressed air energy storage using staged hydraulic conversion, where a VD hydraulic motor-pump 230 is used. The use of the VD hydraulic motor-pump improves the conversion efficiency of the hydraulic-pneumatic energy storage and recovery system and allows a user to achieve near constant expansion or compression power in the system, while maintaining near constant RPM or torque at the shaft of an electric motor-generator.FIG. 10 illustrates the four major energy conversion stages discussed above (compressedgas energy 201,hydraulic energy 202,mechanical energy 203, and electrical energy 204). In addition,FIG. 10 graphically depicts the various operational parameters of the system, such as piston position, power, pressure, flow, torque, RPM, current and voltage versus time for those regions. It should be noted that for simplicity of description, the case of expansion (compressed air energy storage and recovery system discharge) is displayed and described for the graphs inFIG. 10 , but the case of compression (system charging) can be imagined by reversing the time axis on the various plots. - Starting in the compressed
gas energy 201 stage, a set amount of compressed gas is admitted and then expanded in a pneumatic hydraulic device such as theaccumulator 210 driving hydraulic fluid through the hydraulic motor-pump 230. The hydraulic fluid pressure (directly related to compressed gas pressure) falls as a function of time as indicated in the first half ofgraph 420. For all graphs, two expansions are shown for the time scale. At the mid-point in time, a second pneumatic hydraulic device such asintensifier 220 admits and expands a fixed amount of compressed gas. For a VD hydraulic motor-pump 230, the flow rate is controlled by both by the RPM and the displacement per revolution of the motor. - The displacement per revolution of the motor can be controlled in a VD motor-pump. By using pressure, piston position, power, or other current operational information, the flow rate can be set in such a way as to increase with decreasing pressure as shown in
graph 421, by increasing the displacement per revolution. In this instance, a control system is implemented to maintain a nearly constant RPM as indicated ingraph 431. Piston speed inaccumulator 210 changes with flow rate, and thus piston position is related in an integral fashion to flow rate as indicated ingraph 410. As hydraulic power is pressure times flow rate, power varies as a function of time as the product ofgraph 420 andgraph 421 as indicated ingraph 422. For the VD hydraulic motor-pump 230, hydraulic motor-pump output torque is related to pressure,graph 420, times the displacement as a function of time (a fixed RPM displacement has the same curve as flow as shown in graph 421) as indicated ingraph 430. Hydraulic motor-pump 230 output RPM is related to flowgraph 421 as indicated ingraph 431. - Similarly, converting
mechanical energy 203 toelectrical energy 204, electric motor-generator 240 current is related totorque graph 430 as indicated ingraph 440. Electric motor-generator 240 voltage is related toRPM graph 431 as indicated ingraph 441. Power in eachcompressed gas energy 201,hydraulic energy 202,mechanical energy 203, andelectrical energy 204 stages is closely related, scaled by efficiencies of conversions, and fall with time. By maintaining a constant RPM via control of the VD hydraulic motor, output voltage from the electric motor-generator 240 can be matched to the required output, such as the electrical grid power. By matching voltage and frequency with the desired output,power electronics 250 can be removed from the system, saving substantial system costs. Short-term energy storage devices, such as ultracapacitors, could be used to smooth current 440 andpower output 442 as a function of time. As the efficiency of the electric motor-generator 240 is dependent on operating torque and RPM, by limiting the variation in torque and RPM to operation operated over a narrow or fixed range, mechanical to electrical conversion can be increased. -
FIG. 11 depicts generally the major components related to conversion efficiency for compressed air energy storage using staged hydraulic conversion, where a VD hydraulic motor-pump 230 is used.FIG. 11 illustrates the four major energy conversion stages discussed above and graphically depicts the various operational parameters, such as piston position, power, pressure, flow, torque, RPM, current and voltage versus time for those regions.FIG. 11 is closely related toFIG. 10 , but shows the full potential of an optimized control scheme for the VD hydraulic motor-pump 230. It should be noted that for simplicity of description, the case of expansion (compressed air energy storage and recovery system discharge) is displayed and described for the graphs inFIG. 11 , but the case of compression (system charging) can be imagined by reversing the time axis on the various plots. - Starting in
region 201, a set amount of compressed gas is admitted and then expanded in a pneumatic hydraulic device, such as anaccumulator 210 driving hydraulic fluid through the hydraulic motor-pump 230. The hydraulic fluid pressure (directly related to compressed gas pressure) falls as a function of time as indicated in the first half ofgraph 520. For all graphs, two expansions are shown for the time scale. At the mid-point in time, a second pneumatic hydraulic device such as anintensifier 220 admits and expands a fixed amount of compressed gas. For a VD hydraulic motor-pump 230, the flow rate is controlled by both the RPM and the displacement per revolution of the motor. - The displacement per revolution of the motor can be controlled in a VD motor-pump. By using pressure, piston position, power, or other current operational information, the flow rate can be set in such a way as to increase with decreasing pressure as shown in
graph 521 by increasing the displacement per revolution. In this instance, as opposed toFIG. 10 , a control system is implemented to maintain a nearly constant torque or RPM as indicated ingraph 530 andgraph 531. Piston speed in theaccumulator 210 changes with flow rate, and thus piston position is related in an integral fashion to flow rate as indicated ingraph 510. As hydraulic power is pressure times flow rate, power can be made constant as indicated in graph 522 if pressure varies inversely with flow rate as a function of time as indicated ingraph 520 andgraph 521. For theVD motor 230, hydraulic motor output torque is related to pressure,graph 520, times the displacement as a function of time (a fixed RPM displacement has the same curve as flow as shown in graph 521) as indicated ingraph 530. Hydraulic motor output RPM is related to flow 521 as indicated in 531. - Similarly, converting mechanical 203 to
electrical energy 204, electric motor-generator 240 current is related totorque graph 530 as indicated ingraph 540. Electric motor-generator 240 voltage is related toRPM graph 531 as indicated ingraph 541. Power in each stage: compressedgas energy 201,hydraulic energy 202,mechanical energy 203, andelectrical energy 204, are closely related, scaled by efficiencies of conversions, and fall with time. By maintaining a constant torque and RPM via control of the VD hydraulic motor-pump 230 displacement, output voltage from 240 can be matched to the required output, such as the electrical grid power. By matching voltage and frequency with the desired output, power electronics can be removed from the system, saving substantial system costs. Further, by maintaining a constant power output as a function of time over each cycle, no limited short-term energy storage devices, such as ultracapacitors, would be needed to smooth current,graph 540, and power output,graph 542 as a function of time. As the efficiency of the electric motor-generator 240 is dependent on operating torque and RPM, by limiting the variation in torque and RPM to operation operated over a narrow or fixed range, mechanical to electrical conversion can be increased. -
FIG. 12 depicts an alternative arrangement of the major components related to the systems and methods for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile, in this case using a VD motor-pump and open loop control system. Similar to those described above (see, e.g.,FIGS. 2-7 ), the major regions illustrated inFIG. 12 include a source of pressurizedhydraulic fluid 101, such as a hydraulic-pneumatic accumulator or system as described above, which is driving a VDhydraulic motor 110 providing rotary motion (as indicated by arrow 121) of anoutput shaft 120. In this illustration, the outlet of themotor 110 is at low pressure and is directed to ahydraulic fluid reservoir 102; however, the outlet could be directed back to the system providing the source of pressurizedhydraulic fluid 101. The displacement ofmotor 110 is controlled viadisplacement controller 132. -
FIG. 13 depicts an alternative arrangement of the major components related to the systems and methods for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile, in this case using a VD motor-pump and a closed loop control system. Similar to those described above, the major regions illustrated inFIG. 13 include a source of pressurizedhydraulic fluid 101, which is driving a VDhydraulic motor 110 providing rotary motion (arrow 121) of anoutput shaft 120. In this illustration, the outlet of themotor 110 is at low pressure and is directed to ahydraulic fluid reservoir 102, but could be returned to the system providing the source of pressurizedhydraulic fluid 101. The displacement of themotor 110 is controlled viadisplacement controller 132, which is based on RPM and/or torque measurements from a RPM/torque sensor 134. -
FIGS. 14A-14C are graphical representations of the hydraulic pressure, flow rate, and motor output power for a single pressure profile for a representative pressure range related to the system and method for providing constant power, RPM, and torque from a widely-varying pressure hydraulic input ofFIG. 13 . As shown inFIG. 14A , a pressure profile is depicted for a simulated system using a hydraulic pneumatic accumulator with an initial pressure of 3000 psi. As the compressed gas expands in the accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. The VD hydraulic motor displacement is changed such that RPM and torque are nearly constant, increasing hydraulic flow rate through the motor, as shown inFIG. 14B , as pressure decreases. In this way, power is kept nearly constant as a function of time as shown inFIG. 14C . -
FIGS. 15A-15E are graphical representations of the hydraulic pressure, motor displacement, motor RPM, motor torque, and motor output power for a series of pressure profiles for an example cyclic operation of the system and method for providing constant power, RPM, and torque from a widely-varying pressure hydraulic input ofFIG. 13 . InFIG. 15A , a set of three cyclical pressure profiles are shown for the simulated process where successive hydraulic pneumatic accumulators are discharged with an initial pressure of 3000 psi. As the compressed gas expands in each successive accumulator forcing out hydraulic fluid, the pressure falls from 3000 psi to approximately 300 psi. The displacement setting of the VD hydraulic motor is controlled in this example by a PID controller set to achieve constant RPM. As shown inFIGS. 14A-14C , the displacement and thus hydraulic flow increase with decreasing pressure, as shown inFIG. 15B . In this way, RPM, torque, and power are kept nearly constant as a function of time as shown inFIGS. 15C-15E , respectively. InFIGS. 15A-15E , closed-loop feedback on RPM provides a nearly constant power output, except during times of transition switching between accumulators. This switching between accumulators is done in a predictable fashion. -
FIG. 16 depicts an alternative arrangement of the major components related to the systems and methods for providing constant power, RPM, and torque from a hydraulic input having a widely-varying pressure profile, in this case using a VD motor-pump and a control system using predictive information and feedback. Similar to those described above, the major regions illustrated inFIG. 16 include a source of pressurizedhydraulic fluid 101, which is driving a VDhydraulic motor 110 providing rotary motion (arrow 121) of anoutput shaft 120. In this illustration, the outlet of themotor 110 is at low pressure and is directed to ahydraulic fluid reservoir 102, but could be returned to the system providing the source of pressurizedhydraulic fluid 101. The displacement of themotor 110 is controlled viadisplacement controller 132, which is based on computed inputs from thesystem controller 136. Thesystem controller 136 incorporates predictive information based on current system parameters (such as RPM/torque measurements from a RPM/torque sensor 134, as well as piston positions, pressures, and/or temperatures) and procedures such as switching pressures to set displacement such that variations in output around state changes can be minimized. -
FIG. 17A is a schematic diagram of a hydraulic drivetrain including a single fluid power source and a single fluid power consumer, in which the fluid power consumer is a FD hydraulic motor. A drivingmachine 604 is used to turn ashaft 605 powering aVD pump 606 that pumps fluid from atank 602 into a high-pressure line 601. Fluid from thehigh pressure line 601 flows through a FDhydraulic motor 610 and back into thetank 602. Themotor 610 converts the fluid power into mechanical power, drivingshaft 663 and powering the drivenmachine 660. - The equation depicted in
FIG. 17B shows the torque, pressure, and displacement relationship of FDhydraulic motor 610. In this case, thedisplacement 690 ofmotor 610 is constant and fixed. Therefore, thepressure 680 in thehigh pressure line 601 and experienced bymotor 610 must be increased or decreased to increase or decrease theoutput torque 670 of themotor 610. Indrivetrain 600, this is accomplished by adjusting thedisplacement 607 ofpump 606, which increases the fluid power provided toline 601. -
FIG. 18A is a schematic diagram of a hydraulic drivetrain including a single fluid power source and multiple fluid power consumers, in which the fluid power consumers are FD hydraulic motors. A drivingmachine 704 is used to turn ashaft 705 powering aVD pump 706 that pumps fluid from atank 702 into a high-pressure line 701. Fluid from thehigh pressure line 701 flows through FDhydraulic motors tank 702. Themotors shafts machines - The equation depicted in
FIG. 18B shows the torque, pressure, and displacement relationship of the FDhydraulic motors displacements motors pressures high pressure lines motors motors motors pressure line 701, which therefore cannot be used to individually control the outputs of themotors line 601 inFIG. 17A can control the output ofmotor 610. Therefore, the pressure in the high-pressure line 701 is held constant or nearly constant by adjusting thedisplacement 707 ofpump 706, which increases the fluid power provided toline 701. Ahydraulic accumulator 703 is used to reduce pressure fluctuations. Since there are multiple fluid power consumers indrivetrain system 700, pressure-reducingvalves pressures fluid lines motors output torques valves -
FIG. 19A is a schematic of a hydraulic drivetrain including a single fluid power source and multiple fluid power consumers, in which the fluid power consumers are VD hydraulic motors. VD hydraulic motors were developed to provide torque control from a constant or nearly constant pressure fluid power source without the need for throttling valves. By eliminating the energy losses associated with throttling control valves, system efficiencies are greatly increased. - A driving
machine 804 is used to turn ashaft 805 powering aVD pump 806 that pumps fluid from thetank 802 into the high-pressure line 801. Fluid from thehigh pressure line 801 flows through VDhydraulic motors 811, 812 and back to thetank 802. Themotors 811, 812 convert the fluid power into mechanical power, drivingshafts 863, 864 to power the drivenmachines drivetrain 700 inFIG. 18A , both fluid power consumers inFIG. 19A ,motors 811, 812, are affected by the pressure in the high-pressure line 801, which therefore cannot be used to individually control the outputs of themotors 811, 812 the way the pressure inline 601 inFIG. 17A can control the output ofmotor 610. Therefore, the pressure in the high-pressure line 801 is held constant or nearly constant by adjusting thedisplacement 807 ofpump 806, which increases the fluid power provided toline 801. Ahydraulic accumulator 803 is used to reduce pressure fluctuations. - The equation depicted in
FIG. 19B shows the torque, pressure, and displacement relationship of the VDhydraulic motors 811, 812. In this case, thedisplacements 891, 892 of themotors 811, 812 are variable and can be controlled bydisplacement controls 831, 832. Therefore, although thepressures 881, 882 in thehigh pressure line 801 that are experienced by themotors 811, 812 are constant or near constant, thedisplacements 881, 882 of themotors 811, 812 can be increased or decreased via displacement controls 831, 832, thus increasing or decreasing the output torques 871, 872 of themotors 811, 812 to accommodate varying loads on theshafts 863, 864 required by the drivenmachines - In the hydraulic systems shown in
FIG. 17A ,FIG. 18A , andFIG. 19A , either thepressures hydraulic motor displacements 891, 892 were dynamically changed in order to dynamically change the motor output torques 670, 771, 772, 871, 872 to match the required torque demand from the drivenmachines -
FIG. 20A depicts an embodiment of a hydraulic drivetrain in which the driven machine requires constant torque and the displacement of the VD hydraulic motor is controlled to account for changes in the motor inlet pressure, which is non-constant and non-controllable. As shown, thehydraulic motor 910 is powered by a non-controlled,non-constant pressure source 901, such as, for example, the compressed gas energy storage and recovery system using staged hydraulic conversion described above. Fluid flows from thenon-constant pressure source 901 through the VDhydraulic motor 910 and intotank 902. Themotor 910 converts the fluid power into mechanical power, driving ashaft 963 and powering a drivenmachine 960 that requires constant or near constant input torque. In this case, the pressure differential 980 experienced by themotor 910 is provided by thenon-constant pressure source 901, and is thus non-constant and non-controlled. In this embodiment,displacement 930 is actively controlled to be inversely proportional to the pressure differential 980 in order to compensate for the varying nature of the pressure input and provide the constant or near constantmotor torque output 970 required by the drivenmachine 960. See the equation depicted inFIG. 20B , which shows the torque, pressure, and displacement relationship for the hydraulic motor inFIG. 20A . -
FIG. 21 is a schematic representation of an alternative embodiment of a system and method for improving drivetrain efficiency for a compressed gas energy storage using hydraulic conversion to provide a constant output. Thesystem 2100 is integrated with a hydraulic motor-pump 2110 having one each of a high pressure and low pressure input/output, with a series of pistons each driven using a computer controlled valve actuation scheme to allow for variable displacement operation at high efficiency, and described with respect toFIG. 22 . -
FIG. 22 depicts the hydraulic motor-pump 2110, having one each of a high pressure and low pressure input/output 2130 and 2140, with a series of pistons each driven using a computer controlled valve actuation scheme to allow for variable displacement operation at high efficiency. The major components include sixradial piston assemblies 2110 a-f, each composed of a piston 2111 attached to an off-center rotating cam 2120 that turns acenter axle 2121. Each piston 2111 reciprocates in a housing 2112 that is allowed to pivot about a fixed end 2113. High pressure hydraulic fluid, which is brought to/from the motor-pump 2110 through a high pressure hydraulic port 2130, is distributed to/from eachpiston assembly 2110 a-f through high pressure lines 2132. Likewise, low pressure hydraulic fluid is brought to/from the motor-pump 2110 through a low pressurehydraulic port 2140 and is distributed to/from eachpiston assembly 2110 a-f through low pressure lines 2142. - As the
cam 2120 rotates, feedback from motor-pump parameters such as cam position, RPM, torque, and pressure is fed into acontroller 2150 that actuates high speed valves 2131, 2141 through control lines 2133, 2143. Depending on the desired motor-pump displacement per revolution, high pressure valves 2131 may or may not be actuated (to an open position) each time thecam 2120 forces the piston 2111 near the top of the housing 2112. When the high pressure valve 2131 is not actuated (to an open position), the low pressure valve remains open allowing low pressure fluid to freely enter and exit the housing resulting in minimal fluid drag. Unlike most current commercially available VD motor-pumps, the piston always completes a full stroke, thereby increasing motor-pump efficiency. Likewise, by precision timing, the motor-pump can achieve high efficiency over a broad range of per revolution displacements. The motor-pump 2110 depicted inFIG. 22 has a radial piston layout with six pistons; however, various implementations of the systems and methods described herein may use a motor-pump that includes more or less pistons and/or an axial piston design. One implementation of this motor-pump is the “Digital Displacement” motor-pump designed by Artemis IP in Edinburgh, Scotland. - Referring back to
FIG. 21 , the compressed gas energy storage and recovery system illustrated herein consists of compressed gas storage vessels (or caverns) 2102 connected to ahydraulic conversion system 2101, such as those described above. For example, the hydraulic conversion system may consist of one or more hydraulicpneumatic accumulators 2116 and one or more hydraulicpneumatic intensifiers 2118. The air side of the hydraulicpneumatic accumulator 2116 is connected to the compressedgas storage vessels 2102 and the hydraulicpneumatic intensifier 2118 via air lines with shut-offvalves 2106. The air side of the hydraulicpneumatic intensifier 2116 is also in communication with the ambient environment through a vent port and shut-offvalve 2106. The hydraulic outputs ofaccumulator 2116 andintensifier 2118 are routed through a four way twoposition valve 2128 to hydraulic motor-pump 2110. As described above, the use of a VD motor-pump in combination with the system for compressed gas energy storage and recovery allows for operation over a broad pressure range while maintaining nearly constant RPM, torque, and power. The digitally controlled motor-pump 2110 described herein allows for a substantially higher efficiency over a broader pressure range than conventional VD motor-pumps. -
FIG. 23 is a schematic representation of an alternative embodiment of a system and method for improving drivetrain efficiency for a compressed gas energy storage using hydraulic conversion to provide a constant power output. Thesystem 2200 is integrated with a hydraulic motor-pump 2210 having two or more high pressure input/outputs, with a series of pistons each driven using a computer controlled valve actuation scheme to allow for variable displacement operation at high efficiency. The hydraulic motor-pump is described with respect toFIG. 24 . -
FIG. 24 is a schematic of the hydraulic motor-pump 2210, having two or more high pressure input/outputs 2240 and 2230, with a series of pistons each driven using a computer controlled valve actuation scheme to allow for variable displacement operation at high efficiency. As previously described, the major components include sixradial piston assemblies 2110 a-f, each composed of a piston 2111 attached to an off-center rotating cam 2120 which turns acenter axle 2121. Each piston 2111 reciprocates in a housing 2112 that is allowed to pivot about a fixed end 2113. High pressure hydraulic fluid, which is brought to/from the motor-pump 2210 through two (or more) high pressure hydraulic ports 2230 bdf and 2230 ace is distributed to/from eachpiston assembly 2110 b,d,f and 2110 a,c,e through high pressure lines 2232 bdf and 2232 ace, respectively. Likewise, low pressure hydraulic fluid is brought to/from the motor-pump 2210 through one or more low pressurehydraulic ports 2240 and is distributed to/from eachpiston assembly 2110 a-f through low pressure lines 2242. - As the
cam 2120 rotates, feedback from motor-pump parameters such as cam position, RPM, torque, and pressure is fed into acontroller 2150 which actuates high speed valves 2131, 2141 through control lines 2133, 2143. Depending on the desired motor-pump displacement per revolution, high pressure valves 2131 may or may not be actuated (to an open position) each time thecam 2120 forces the piston 2111 near the top of the housing 2112. When the high pressure valve 2131 is not actuated (to an open position), the low pressure valve remains open allowing low pressure fluid to freely enter and exit the housing resulting in minimal fluid drag. As previously discussed, the piston always completes a full stroke, thereby increasing motor-pump efficiency. Likewise, by precision timing, the motor-pump can achieve high efficiency over a broad range of per revolution displacements. Again, the motor-pump is depicted as a radial piston layout with six piston assemblies, but motor-pumps having different layouts and quantities of piston assemblies and are contemplated and within the scope of the invention. Additionally, by using multiple input/output ports attached to different piston assemblies, multiple input/output pressures and flows can be achieved within a single motor-pump. As shown inFIG. 24 , all piston sizes are shown as the same; however, piston sizes can vary. For example,piston assemblies 2110 a, c, e can be a different size thanpiston assemblies 2110 b, d, f. - Referring back to
FIG. 23 , the compressed gas energy storage and recovery system illustrated herein similarly consists of compressed gas storage vessels (or caverns) 2102 connected to ahydraulic conversion system 2201, such as those described above. As the hydraulic motor-pump 2210 has multiple high pressure ports,system 2201 has multiple, different hydraulic fluid pressure streams, allowing for their combination within asingle motor 2210. The stagedhydraulic conversion system 2201 may consist of two or more accumulator and intensifier arrangements. As shown, a first arrangement consists of one or more hydraulicpneumatic accumulators 2116 and one or more hydraulicpneumatic intensifiers 2118. The air side of the first arrangement of hydraulicpneumatic accumulators 2116 is connected to the compressedgas storage vessels 2102 and the hydraulicpneumatic intensifiers 2118 via air lines with shut-offvalves 2106 and the air side of hydraulicpneumatic intensifiers 2118 is also in communication with the ambient environment through a vent port and shut-offvalve 2106. The hydraulic outputs of the first arrangement are routed through a four way twoposition valve 2128 to one of the high pressure ports of the hydraulic motor-pump 2210. - The
system 2201 also includes a second arrangement of accumulators and intensifiers. The second arrangement also includes one or more hydraulicpneumatic accumulators 2116 and one or more hydraulicpneumatic intensifiers 2118. The air side of the second arrangement of the hydraulicpneumatic accumulators 2116 is connected to the compressedgas storage vessels 2102 and the hydraulicpneumatic intensifiers 2118 via air lines with shut-offvalves 2106 and the air side of hydraulicpneumatic intensifiers 2118 is also in communication with the ambient environment through a vent port and shut-offvalve 2106. The hydraulic outputs of the second arrangement are routed through a four way twoposition valve 2128 to a second of the high pressure ports of the hydraulic motor-pump 2210. Likewise, additional high pressure ports may be added to a single digitally controlled motor-pump, allowing for additional pressure streams to be combined within a single motor-pump. Because the motor-pump 2210 has integrated digitally controlled valving (2131 a-f and 2141 a-f inFIGS. 22 and 24 ), fewer hydraulic valves can be used in thehydraulic conversion system 2102, thereby reducing cost and increasing functionality. As described above, the use of a VD motor-pump in combination with the system for compressed gas energy storage allows for operation over a broad pressure range while maintaining nearly constant RPM, torque, and power and the digitally controlled motor-pump 2210 allows for a substantially higher efficiency over a broader pressure range than conventional VD motor-pumps. Additionally, by combining multiple pressure streams, the effects of broader pressure ranges in relation to power and flow rates can be further diminished, further improving performance. - Having described certain embodiments of the invention, it will be apparent to those of ordinary skill in the art that other embodiments incorporating the concepts disclosed herein may be used without departing from the spirit and scope of the invention. The described embodiments are to be considered in all respects as only illustrative and not restrictive.
- Moreover, it will also be apparent to those of ordinary skill in the art that the exemplary systems described herein, as well as other embodiments, can be operated reversibly, that is, not only to produce electrical energy from the potential energy of pressurized gas but also to produce stored pressurized gas using electrical energy.
Claims (24)
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Cited By (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110219760A1 (en) * | 2008-04-09 | 2011-09-15 | Mcbride Troy O | Systems and methods for energy storage and recovery using compressed gas |
WO2011135522A2 (en) * | 2010-04-28 | 2011-11-03 | Abraham Bauer | Hydraulic power converter |
US8171728B2 (en) | 2010-04-08 | 2012-05-08 | Sustainx, Inc. | High-efficiency liquid heat exchange in compressed-gas energy storage systems |
US8191362B2 (en) | 2010-04-08 | 2012-06-05 | Sustainx, Inc. | Systems and methods for reducing dead volume in compressed-gas energy storage systems |
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US9243558B2 (en) | 2012-03-13 | 2016-01-26 | Storwatts, Inc. | Compressed air energy storage |
JP5795286B2 (en) * | 2012-05-22 | 2015-10-14 | 株式会社堀場製作所 | Exhaust gas analysis system |
US8726629B2 (en) | 2012-10-04 | 2014-05-20 | Lightsail Energy, Inc. | Compressed air energy system integrated with gas turbine |
CN102996575A (en) * | 2012-10-12 | 2013-03-27 | 安徽蓝德仪表有限公司 | High-pressure gas-liquid conversion pressing mechanism |
US8851043B1 (en) | 2013-03-15 | 2014-10-07 | Lightsail Energy, Inc. | Energy recovery from compressed gas |
US9074577B2 (en) | 2013-03-15 | 2015-07-07 | Dehlsen Associates, Llc | Wave energy converter system |
CH708072A1 (en) * | 2013-05-17 | 2014-11-28 | Swiss Green Systems Sagl | Device for the production of electrical energy. |
WO2015032137A1 (en) * | 2013-09-09 | 2015-03-12 | 王曙光 | Wind power valley electricity pneumatic energy-storage cyclic water pumping system |
KR101588790B1 (en) * | 2014-07-29 | 2016-01-26 | 현대자동차 주식회사 | Vehicle control system having motor |
CN105539049B (en) * | 2016-03-01 | 2018-06-08 | 谢长溪 | A kind of automobile absorber real-time monitoring system |
US10231390B2 (en) | 2016-05-24 | 2019-03-19 | Lindsay Corporation | Irrigation system with variable gear ratio transmissions |
CN108036980B (en) * | 2017-11-28 | 2020-05-19 | 宁波江北文增新材料科技有限公司 | New material composition analytical equipment |
US11031149B1 (en) * | 2018-02-13 | 2021-06-08 | AGI Engineering, Inc. | Nuclear abrasive slurry waste pump with backstop and macerator |
CN112673136B (en) * | 2018-09-10 | 2023-06-09 | 阿尔特弥斯智能动力有限公司 | Apparatus with hydraulic machine controller |
CN110707705B (en) * | 2019-10-22 | 2023-01-17 | 太原理工大学 | Power flow sequence analysis model of electric-gas coupling comprehensive energy system |
CN113517702B (en) * | 2021-04-26 | 2022-02-08 | 南京邮电大学 | Emergency control method and system for source-storage-load adjustment-switching linkage |
CN114094568B (en) * | 2021-10-28 | 2023-06-09 | 国网湖南省电力有限公司 | Fluctuating pressure power generation control method and system of power generation-energy storage system |
Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4206608A (en) * | 1978-06-21 | 1980-06-10 | Bell Thomas J | Natural energy conversion, storage and electricity generation system |
BE898225A (en) * | 1983-11-16 | 1984-03-16 | Fuchs Julien | Hydropneumatic power unit - has hydraulic motor fed by pump driven by air motor from vessel connected to compressor on hydromotor shaft |
US5819635A (en) * | 1996-12-19 | 1998-10-13 | Moonen; Raymond J. | Hydraulic-pneumatic motor |
US6651545B2 (en) * | 2001-12-13 | 2003-11-25 | Caterpillar Inc | Fluid translating device |
US6718761B2 (en) * | 2001-04-10 | 2004-04-13 | New World Generation Inc. | Wind powered hydroelectric power plant and method of operation thereof |
US7000389B2 (en) * | 2002-03-27 | 2006-02-21 | Richard Laurance Lewellin | Engine for converting thermal energy to stored energy |
US20090317266A1 (en) * | 2006-07-27 | 2009-12-24 | William Hugh Salvin Rampen | Digital hydraulic pump/motor torque modulation system and apparatus |
US20100037604A1 (en) * | 2006-07-21 | 2010-02-18 | William Hugh Salvin Rampen | Fluid power distribution and control system |
US20100133903A1 (en) * | 2007-05-09 | 2010-06-03 | Alfred Rufer | Energy Storage Systems |
US20100257862A1 (en) * | 2007-10-03 | 2010-10-14 | Isentropic Limited | Energy Storage |
US7932620B2 (en) * | 2008-05-01 | 2011-04-26 | Plant Jr William R | Windmill utilizing a fluid driven pump |
Family Cites Families (675)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US114297A (en) | 1871-05-02 | Improvement in combined punching and shearing machines | ||
US224081A (en) | 1880-02-03 | Air-compressor | ||
US233432A (en) | 1880-10-19 | Air-compressor | ||
US1353216A (en) | 1918-06-17 | 1920-09-21 | Edward P Carlson | Hydraulic pump |
US1635524A (en) | 1925-11-09 | 1927-07-12 | Nat Brake And Electric Company | Method of and means for cooling compressors |
US1681280A (en) | 1926-09-11 | 1928-08-21 | Doherty Res Co | Isothermal air compressor |
US2025142A (en) | 1934-08-13 | 1935-12-24 | Zahm & Nagel Co Inc | Cooling means for gas compressors |
US2042991A (en) | 1934-11-26 | 1936-06-02 | Jr James C Harris | Method of and apparatus for producing vapor saturation |
US2141703A (en) * | 1937-11-04 | 1938-12-27 | Stanolind Oil & Gas Co | Hydraulic-pneumatic pumping system |
US2280845A (en) | 1938-01-29 | 1942-04-28 | Humphrey F Parker | Air compressor system |
US2280100A (en) | 1939-11-03 | 1942-04-21 | Fred C Mitchell | Fluid pressure apparatus |
US2404660A (en) | 1943-08-26 | 1946-07-23 | Wilfred J Rouleau | Air compressor |
US2486081A (en) | 1944-07-27 | 1949-10-25 | Hartford Nat Bank & Trust Co | Multicylinder refrigerating machine |
US2420098A (en) | 1944-12-07 | 1947-05-06 | Wilfred J Rouleau | Compressor |
US2539862A (en) | 1946-02-21 | 1951-01-30 | Wallace E Rushing | Air-driven turbine power plant |
US2628564A (en) | 1949-12-01 | 1953-02-17 | Charles R Jacobs | Hydraulic system for transferring rotary motion to reciprocating motion |
GB722524A (en) | 1950-11-17 | 1955-01-26 | Paulin Gosse | Improvements in apparatus for the industrial compression of gases or vapours |
US2712728A (en) | 1952-04-30 | 1955-07-12 | Exxon Research Engineering Co | Gas turbine inter-stage reheating system |
US2813398A (en) | 1953-01-26 | 1957-11-19 | Wilcox Roy Milton | Thermally balanced gas fluid pumping system |
US2829501A (en) | 1953-08-21 | 1958-04-08 | D W Burkett | Thermal power plant utilizing compressed gas as working medium in a closed circuit including a booster compressor |
GB772703A (en) | 1954-12-28 | 1957-04-17 | Soc Es Energie Sa | Improvements in a gas-generator comprising an auxiliary gas turbine adapted to driveat least one auxiliary device of the generator |
US2880759A (en) | 1956-06-06 | 1959-04-07 | Bendix Aviat Corp | Hydro-pneumatic energy storage device |
US3100965A (en) | 1959-09-29 | 1963-08-20 | Charles M Blackburn | Hydraulic power supply |
US3041842A (en) | 1959-10-26 | 1962-07-03 | Gustav W Heinecke | System for supplying hot dry compressed air |
US3236512A (en) * | 1964-01-16 | 1966-02-22 | Kirsch Jerry | Self-adjusting hydropneumatic kinetic energy absorption arrangement |
US3269121A (en) | 1964-02-26 | 1966-08-30 | Bening Ludwig | Wind motor |
US3538340A (en) | 1968-03-20 | 1970-11-03 | William J Lang | Method and apparatus for generating power |
US3608311A (en) | 1970-04-17 | 1971-09-28 | John F Roesel Jr | Engine |
US3650636A (en) | 1970-05-06 | 1972-03-21 | Michael Eskeli | Rotary gas compressor |
US3648458A (en) | 1970-07-28 | 1972-03-14 | Roy E Mcalister | Vapor pressurized hydrostatic drive |
US3704079A (en) | 1970-09-08 | 1972-11-28 | Martin John Berlyn | Air compressors |
US3677008A (en) | 1971-02-12 | 1972-07-18 | Gulf Oil Corp | Energy storage system and method |
FR2125680A5 (en) | 1971-02-16 | 1972-09-29 | Rigollot Georges | |
US3672160A (en) | 1971-05-20 | 1972-06-27 | Dae Sik Kim | System for producing substantially pollution-free hot gas under pressure for use in a prime mover |
DE2134192C3 (en) | 1971-07-09 | 1979-03-29 | Kraftwerk Union Ag, 4330 Muelheim | Combined gas-steam power plant |
US3958899A (en) | 1971-10-21 | 1976-05-25 | General Power Corporation | Staged expansion system as employed with an integral turbo-compressor wave engine |
US3803847A (en) | 1972-03-10 | 1974-04-16 | Alister R Mc | Energy conversion system |
FR2183340A5 (en) | 1972-05-03 | 1973-12-14 | Rigollot Georges | |
US4676068A (en) | 1972-05-12 | 1987-06-30 | Funk Harald F | System for solar energy collection and recovery |
US4126000A (en) | 1972-05-12 | 1978-11-21 | Funk Harald F | System for treating and recovering energy from exhaust gases |
US4411136A (en) | 1972-05-12 | 1983-10-25 | Funk Harald F | System for treating and recovering energy from exhaust gases |
US3793848A (en) | 1972-11-27 | 1974-02-26 | M Eskeli | Gas compressor |
US3839863A (en) | 1973-01-23 | 1974-10-08 | L Frazier | Fluid pressure power plant |
GB1443433A (en) | 1973-02-12 | 1976-07-21 | Cheynet & Fils | Methods and apparatus for the production of textile fabrics |
US3847182A (en) | 1973-06-18 | 1974-11-12 | E Greer | Hydro-pneumatic flexible bladder accumulator |
US3890786A (en) | 1973-08-31 | 1975-06-24 | Gen Signal Corp | Pneumatic to hydraulic converter with parking brake |
US4027993A (en) | 1973-10-01 | 1977-06-07 | Polaroid Corporation | Method and apparatus for compressing vaporous or gaseous fluids isothermally |
US4041708A (en) | 1973-10-01 | 1977-08-16 | Polaroid Corporation | Method and apparatus for processing vaporous or gaseous fluids |
FR2247631B1 (en) | 1973-10-12 | 1977-05-27 | Maillet Edgard | |
DE2352561C2 (en) | 1973-10-19 | 1983-02-17 | Linde Ag, 6200 Wiesbaden | Method for dissipating the compression heat that arises when compressing a gas mixture |
DE2421398C2 (en) | 1974-05-03 | 1983-11-24 | Audi Nsu Auto Union Ag, 7107 Neckarsulm | Heat engine for driving a motor vehicle |
HU168430B (en) | 1974-04-09 | 1976-04-28 | ||
DE2524891A1 (en) | 1974-06-07 | 1975-12-18 | Nikolaus Laing | METHOD OF DRIVING RAIL VEHICLES AND RAIL VEHICLES WITH THE ENGINE OUTSIDE THE VEHICLE |
US3945207A (en) | 1974-07-05 | 1976-03-23 | James Ervin Hyatt | Hydraulic propulsion system |
US3939356A (en) | 1974-07-24 | 1976-02-17 | General Public Utilities Corporation | Hydro-air storage electrical generation system |
DE2536447B2 (en) | 1974-09-16 | 1977-09-01 | Gebruder Sulzer AG, Winterthur (Schweiz) | SYSTEM FOR STORAGE OF ENERGY OF AN ELECTRICAL SUPPLY NETWORK USING COMPRESSED AIR AND FOR RECYCLING IT |
US3988592A (en) | 1974-11-14 | 1976-10-26 | Porter William H | Electrical generating system |
US3903696A (en) | 1974-11-25 | 1975-09-09 | Carman Vincent Earl | Hydraulic energy storage transmission |
US3991574A (en) | 1975-02-03 | 1976-11-16 | Frazier Larry Vane W | Fluid pressure power plant with double-acting piston |
FR2326595A1 (en) | 1975-02-10 | 1977-04-29 | Germain Fernand | IMPROVED INSTALLATION FOR THE GENERATION OF ELECTRIC ENERGY |
US3952723A (en) | 1975-02-14 | 1976-04-27 | Browning Engineering Corporation | Windmills |
US4008006A (en) | 1975-04-24 | 1977-02-15 | Bea Karl J | Wind powered fluid compressor |
US3948049A (en) | 1975-05-01 | 1976-04-06 | Caterpillar Tractor Co. | Dual motor hydrostatic drive system |
US3952516A (en) | 1975-05-07 | 1976-04-27 | Lapp Ellsworth W | Hydraulic pressure amplifier |
US4118637A (en) * | 1975-05-20 | 1978-10-03 | Unep3 Energy Systems Inc. | Integrated energy system |
US3996741A (en) | 1975-06-05 | 1976-12-14 | Herberg George M | Energy storage system |
FR2345600A1 (en) | 1975-06-09 | 1977-10-21 | Bourquardez Gaston | FLUID BEARING WIND TURBINE |
NL7508053A (en) | 1975-07-07 | 1977-01-11 | Philips Nv | HOT GAS PISTON ENGINE WITH SHAFT COUPLED COMBUSTION AIR FAN. |
US3986354A (en) | 1975-09-15 | 1976-10-19 | Erb George H | Method and apparatus for recovering low-temperature industrial and solar waste heat energy previously dissipated to ambient |
US3998049A (en) | 1975-09-30 | 1976-12-21 | G & K Development Co., Inc. | Steam generating apparatus |
US3999388A (en) | 1975-10-08 | 1976-12-28 | Forenade Fabriksverken | Power control device |
US4030303A (en) | 1975-10-14 | 1977-06-21 | Kraus Robert A | Waste heat regenerating system |
US4204126A (en) | 1975-10-21 | 1980-05-20 | Diggs Richard E | Guided flow wind power machine with tubular fans |
NL7514750A (en) | 1975-12-18 | 1977-06-21 | Stichting Reactor Centrum | WINDMILL INSTALLATION FOR GENERATING ENERGY. |
US4055950A (en) | 1975-12-29 | 1977-11-01 | Grossman William C | Energy conversion system using windmill |
CH593423A5 (en) | 1976-03-15 | 1977-11-30 | Bbc Brown Boveri & Cie | |
US4031702A (en) | 1976-04-14 | 1977-06-28 | Burnett James T | Means for activating hydraulic motors |
FR2351277A1 (en) | 1976-05-11 | 1977-12-09 | Spie Batignolles | SYSTEM FOR TRANSFORMING RANDOM ENERGY FROM A NATURAL FLUID |
DE2732320A1 (en) | 1976-07-19 | 1978-01-26 | Gen Electric | PROCESS AND DEVICE FOR HEAT EXCHANGE FOR THERMAL ENERGY STORAGE |
US4031704A (en) | 1976-08-16 | 1977-06-28 | Moore Marvin L | Thermal engine system |
US4167372A (en) | 1976-09-30 | 1979-09-11 | Unep 3 Energy Systems, Inc. | Integrated energy system |
GB1583648A (en) | 1976-10-04 | 1981-01-28 | Acres Consulting Services | Compressed air power storage systems |
US4170878A (en) | 1976-10-13 | 1979-10-16 | Jahnig Charles E | Energy conversion system for deriving useful power from sources of low level heat |
US4197700A (en) | 1976-10-13 | 1980-04-15 | Jahnig Charles E | Gas turbine power system with fuel injection and combustion catalyst |
IT1073144B (en) | 1976-10-28 | 1985-04-13 | Welko Ind Spa | HYDRAULIC EQUIPMENT FOR THE SUPPLY OF LIQUID AT TWO DIFFERENT PRESSURES TO A HYDRAULIC DEVICE |
US4089744A (en) | 1976-11-03 | 1978-05-16 | Exxon Research & Engineering Co. | Thermal energy storage by means of reversible heat pumping |
US4095118A (en) | 1976-11-26 | 1978-06-13 | Rathbun Kenneth R | Solar-mhd energy conversion system |
DE2655026C2 (en) | 1976-12-04 | 1979-01-18 | Ulrich Prof. Dr.-Ing. 7312 Kirchheim Huetter | Wind energy converter |
CH598535A5 (en) | 1976-12-23 | 1978-04-28 | Bbc Brown Boveri & Cie | |
US4136432A (en) | 1977-01-13 | 1979-01-30 | Melley Energy Systems, Inc. | Mobile electric power generating systems |
US4117342A (en) | 1977-01-13 | 1978-09-26 | Melley Energy Systems | Utility frame for mobile electric power generating systems |
US4110987A (en) | 1977-03-02 | 1978-09-05 | Exxon Research & Engineering Co. | Thermal energy storage by means of reversible heat pumping utilizing industrial waste heat |
CA1128993A (en) | 1977-03-10 | 1982-08-03 | Henry Lawson-Tancred | Electric power generation from non-uniformly operating energy sources |
US4209982A (en) | 1977-04-07 | 1980-07-01 | Arthur W. Fisher, III | Low temperature fluid energy conversion system |
US4104955A (en) | 1977-06-07 | 1978-08-08 | Murphy John R | Compressed air-operated motor employing an air distributor |
FR2394023A1 (en) | 1977-06-10 | 1979-01-05 | Anvar | CALORIFIC ENERGY STORAGE AND RECOVERY INSTALLATION, ESPECIALLY FOR SOLAR POWER PLANTS |
US4109465A (en) | 1977-06-13 | 1978-08-29 | Abraham Plen | Wind energy accumulator |
US4117696A (en) | 1977-07-05 | 1978-10-03 | Battelle Development Corporation | Heat pump |
US4197715A (en) | 1977-07-05 | 1980-04-15 | Battelle Development Corporation | Heat pump |
US4173431A (en) | 1977-07-11 | 1979-11-06 | Nu-Watt, Inc. | Road vehicle-actuated air compressor and system therefor |
US4335867A (en) | 1977-10-06 | 1982-06-22 | Bihlmaier John A | Pneumatic-hydraulic actuator system |
US4124182A (en) | 1977-11-14 | 1978-11-07 | Arnold Loeb | Wind driven energy system |
US4232253A (en) | 1977-12-23 | 1980-11-04 | International Business Machines Corporation | Distortion correction in electromagnetic deflection yokes |
US4189925A (en) | 1978-05-08 | 1980-02-26 | Northern Illinois Gas Company | Method of storing electric power |
EP0008929A1 (en) | 1978-09-05 | 1980-03-19 | John Walter Rilett | Motors and gas supply apparatus therefor |
US4273514A (en) | 1978-10-06 | 1981-06-16 | Ferakarn Limited | Waste gas recovery systems |
US4316096A (en) | 1978-10-10 | 1982-02-16 | Syverson Charles D | Wind power generator and control therefore |
US4348863A (en) | 1978-10-31 | 1982-09-14 | Taylor Heyward T | Regenerative energy transfer system |
US4220006A (en) | 1978-11-20 | 1980-09-02 | Kindt Robert J | Power generator |
US4353214A (en) | 1978-11-24 | 1982-10-12 | Gardner James H | Energy storage system for electric utility plant |
CA1214088A (en) | 1978-12-08 | 1986-11-18 | William S. Heggie | Engine control systems |
US4242878A (en) | 1979-01-22 | 1981-01-06 | Split Cycle Energy Systems, Inc. | Isothermal compressor apparatus and method |
US4246978A (en) | 1979-02-12 | 1981-01-27 | Dynecology | Propulsion system |
US4229661A (en) | 1979-02-21 | 1980-10-21 | Mead Claude F | Power plant for camping trailer |
FR2449805A1 (en) * | 1979-02-22 | 1980-09-19 | Guises Patrick | Compressed air piston engine - has automatic inlet valves and drives alternator for battery and compressor to maintain pressure in the air receiver |
US4237692A (en) | 1979-02-28 | 1980-12-09 | The United States Of America As Represented By The United States Department Of Energy | Air ejector augmented compressed air energy storage system |
SU800438A1 (en) * | 1979-03-20 | 1981-01-30 | Проектно-Технологический Трест"Дальоргтехводстрой" | Pumping-accumulating unit |
US4281256A (en) | 1979-05-15 | 1981-07-28 | The United States Of America As Represented By The United States Department Of Energy | Compressed air energy storage system |
US4503673A (en) * | 1979-05-25 | 1985-03-12 | Charles Schachle | Wind power generating system |
AU5900380A (en) | 1979-06-08 | 1980-12-11 | Payne, B.M.M. | Compressed air system |
US4302684A (en) | 1979-07-05 | 1981-11-24 | Gogins Laird B | Free wing turbine |
IL60721A (en) | 1979-08-07 | 1984-12-31 | Archer John David | Device for utilization of wind energy |
US4317439A (en) | 1979-08-24 | 1982-03-02 | The Garrett Corporation | Cooling system |
US4293323A (en) | 1979-08-30 | 1981-10-06 | Frederick Cohen | Waste heat energy recovery system |
JPS5932662B2 (en) | 1979-08-31 | 1984-08-10 | 株式会社島津製作所 | Wind energy conversion device |
US4299198A (en) | 1979-09-17 | 1981-11-10 | Woodhull William M | Wind power conversion and control system |
US4462213A (en) | 1979-09-26 | 1984-07-31 | Lewis Arlin C | Solar-wind energy conversion system |
US4311011A (en) | 1979-09-26 | 1982-01-19 | Lewis Arlin C | Solar-wind energy conversion system |
US4375387A (en) | 1979-09-28 | 1983-03-01 | Critical Fluid Systems, Inc. | Apparatus for separating organic liquid solutes from their solvent mixtures |
US4354420A (en) | 1979-11-01 | 1982-10-19 | Caterpillar Tractor Co. | Fluid motor control system providing speed change by combination of displacement and flow control |
DE2947258A1 (en) | 1979-11-23 | 1981-05-27 | Daimler-Benz Ag, 7000 Stuttgart | HYDROSTATIC BUBBLE STORAGE |
US4355956A (en) | 1979-12-26 | 1982-10-26 | Leland O. Lane | Wind turbine |
US4341072A (en) | 1980-02-07 | 1982-07-27 | Clyne Arthur J | Method and apparatus for converting small temperature differentials into usable energy |
CH641876A5 (en) | 1980-02-14 | 1984-03-15 | Sulzer Ag | PISTON COMPRESSOR, IN PARTICULAR TO COMPRESS OXYGEN. |
US4275310A (en) | 1980-02-27 | 1981-06-23 | Summers William A | Peak power generation |
US4368775A (en) | 1980-03-03 | 1983-01-18 | Ward John D | Hydraulic power equipment |
YU100980A (en) | 1980-04-11 | 1983-09-30 | Ivo Kolin | Hot gas motor |
US4304103A (en) | 1980-04-22 | 1981-12-08 | World Energy Systems | Heat pump operated by wind or other power means |
US4619225A (en) | 1980-05-05 | 1986-10-28 | Atlantic Richfield Company | Apparatus for storage of compressed gas at ambient temperature |
ES8301330A1 (en) | 1980-07-24 | 1982-12-01 | Central Energetic Ciclonic | System for the obtaining of energy by fluid flows resembling a natural cyclone or anti-cyclone |
US4340822A (en) | 1980-08-18 | 1982-07-20 | Gregg Hendrick J | Wind power generating system |
US4739620A (en) | 1980-09-04 | 1988-04-26 | Pierce John E | Solar energy power system |
RO77965A2 (en) | 1980-10-08 | 1983-09-26 | Chrisoghilos,Vasie A.,Ro | METHOD AND MACHINE FOR OBTAINING QUASIISOTERMIC TRANSFORMATION IN QUASI-ISOTHERMAL COMPRESSION PROCESSES IN PROCESSES OF COMPRESSION OR EXPANSION OF GAS ION OR EXPANSION |
US4370559A (en) | 1980-12-01 | 1983-01-25 | Langley Jr David T | Solar energy system |
US4767938A (en) | 1980-12-18 | 1988-08-30 | Bervig Dale R | Fluid dynamic energy producing device |
US4372114A (en) | 1981-03-10 | 1983-02-08 | Orangeburg Technologies, Inc. | Generating system utilizing multiple-stage small temperature differential heat-powered pumps |
US4446698A (en) | 1981-03-18 | 1984-05-08 | New Process Industries, Inc. | Isothermalizer system |
US4492539A (en) | 1981-04-02 | 1985-01-08 | Specht Victor J | Variable displacement gerotor pump |
US4380419A (en) | 1981-04-15 | 1983-04-19 | Morton Paul H | Energy collection and storage system |
US4593202A (en) | 1981-05-06 | 1986-06-03 | Dipac Associates | Combination of supercritical wet combustion and compressed air energy storage |
US4474002A (en) | 1981-06-09 | 1984-10-02 | Perry L F | Hydraulic drive pump apparatus |
US4421661A (en) | 1981-06-19 | 1983-12-20 | Institute Of Gas Technology | High-temperature direct-contact thermal energy storage using phase-change media |
US4416114A (en) | 1981-07-31 | 1983-11-22 | Martini William R | Thermal regenerative machine |
FR2512881B1 (en) | 1981-09-14 | 1988-02-26 | Colgate Thermodynamics Co | THERMODYNAMIC VOLUMETRIC MACHINE WITH ISOTHERMIC CYCLE |
US4455834A (en) | 1981-09-25 | 1984-06-26 | Earle John L | Windmill power apparatus and method |
US4515516A (en) | 1981-09-30 | 1985-05-07 | Champion, Perrine & Associates | Method and apparatus for compressing gases |
DE3234170C2 (en) | 1981-10-26 | 1985-04-11 | Öko-Energie AG, Zürich | Wind power plant with at least one wing that can be rotated about an axis of rotation |
US5794442A (en) | 1981-11-05 | 1998-08-18 | Lisniansky; Robert Moshe | Adaptive fluid motor control |
US4435131A (en) | 1981-11-23 | 1984-03-06 | Zorro Ruben | Linear fluid handling, rotary drive, mechanism |
US4493189A (en) | 1981-12-04 | 1985-01-15 | Slater Harry F | Differential flow hydraulic transmission |
US4447738A (en) | 1981-12-30 | 1984-05-08 | Allison Johnny H | Wind power electrical generator system |
US4525631A (en) | 1981-12-30 | 1985-06-25 | Allison John H | Pressure energy storage device |
US4476851A (en) | 1982-01-07 | 1984-10-16 | Brugger Hans | Windmill energy system |
US4454720A (en) | 1982-03-22 | 1984-06-19 | Mechanical Technology Incorporated | Heat pump |
US4478553A (en) | 1982-03-29 | 1984-10-23 | Mechanical Technology Incorporated | Isothermal compression |
DE3211598A1 (en) | 1982-03-30 | 1983-11-03 | Daimler-Benz Ag, 7000 Stuttgart | PISTON AIR PRESSER |
EP0091801A3 (en) | 1982-04-14 | 1984-02-29 | Unimation Inc. | Energy recovery system for manipulator apparatus |
KR840000180Y1 (en) | 1982-05-19 | 1984-02-07 | 임동순 | Spindle press roller of paper pipe |
US4496847A (en) | 1982-06-04 | 1985-01-29 | Parkins William E | Power generation from wind |
AU552698B2 (en) | 1982-06-04 | 1986-06-12 | William Edward Parkins | Wind motor regulation |
US4489554A (en) | 1982-07-09 | 1984-12-25 | John Otters | Variable cycle stirling engine and gas leakage control system therefor |
FR2530209A1 (en) | 1982-07-16 | 1984-01-20 | Renault Vehicules Ind | OLEOPNEUMATIC ENERGY TANK FOR ACCUMULATING THE BRAKE ENERGY RECOVERED ON A VEHICLE |
EP0104034A1 (en) | 1982-09-20 | 1984-03-28 | JAMES HOWDEN & COMPANY LIMITED | Wind turbines |
US4491739A (en) | 1982-09-27 | 1985-01-01 | Watson William K | Airship-floated wind turbine |
US4454429A (en) | 1982-12-06 | 1984-06-12 | Frank Buonome | Method of converting ocean wave action into electrical energy |
SE437861B (en) | 1983-02-03 | 1985-03-18 | Goran Palmers | DEVICE FOR MEDIUM HYDRAULIC CYLINDER OPERATED MACHINERY WITH ONE OF A DRIVE CELL THROUGH AN ENERGY CUMULATOR DRIVE PUMP |
US4530208A (en) | 1983-03-08 | 1985-07-23 | Shigeki Sato | Fluid circulating system |
HU190071B (en) * | 1983-03-10 | 1986-08-28 | Gyimesi,Janos,Hu | Wind engine as well as fluid furthering device operable particularly by wind engine |
US4589475A (en) | 1983-05-02 | 1986-05-20 | Plant Specialties Company | Heat recovery system employing a temperature controlled variable speed fan |
US4653986A (en) * | 1983-07-28 | 1987-03-31 | Tidewater Compression Service, Inc. | Hydraulically powered compressor and hydraulic control and power system therefor |
US4710100A (en) | 1983-11-21 | 1987-12-01 | Oliver Laing | Wind machine |
US4585039A (en) | 1984-02-02 | 1986-04-29 | Hamilton Richard A | Gas-compressing system |
US4547209A (en) | 1984-02-24 | 1985-10-15 | The Randall Corporation | Carbon dioxide hydrocarbons separation process utilizing liquid-liquid extraction |
US4877530A (en) | 1984-04-25 | 1989-10-31 | Cf Systems Corporation | Liquid CO2 /cosolvent extraction |
US6327994B1 (en) | 1984-07-19 | 2001-12-11 | Gaudencio A. Labrador | Scavenger energy converter system its new applications and its control systems |
US4706456A (en) | 1984-09-04 | 1987-11-17 | South Bend Lathe, Inc. | Method and apparatus for controlling hydraulic systems |
NL8402899A (en) | 1984-09-21 | 1986-04-16 | Rietschoten & Houwens Tech Han | HYDRAULIC SWITCHING WITH SAVING TANK. |
US4651525A (en) | 1984-11-07 | 1987-03-24 | Cestero Luis G | Piston reciprocating compressed air engine |
SE446852B (en) | 1984-11-28 | 1986-10-13 | Sten Lovgren | POWER UNIT |
IT1187318B (en) | 1985-02-22 | 1987-12-23 | Franco Zanarini | VOLUMETRIC ALTERNATE COMPRESSOR WITH HYDRAULIC OPERATION |
EP0196690B1 (en) | 1985-03-28 | 1989-10-18 | Shell Internationale Researchmaatschappij B.V. | Energy storage and recovery |
DE3667705D1 (en) | 1985-08-06 | 1990-01-25 | Shell Int Research | STORAGE AND RECOVERY OF ENERGY. |
US4735552A (en) | 1985-10-04 | 1988-04-05 | Watson William K | Space frame wind turbine |
US5182086A (en) | 1986-04-30 | 1993-01-26 | Henderson Charles A | Oil vapor extraction system |
JPS62258207A (en) | 1986-04-30 | 1987-11-10 | Sumio Sugawara | Combined hydraulic cylinder device |
US4760697A (en) | 1986-08-13 | 1988-08-02 | National Research Council Of Canada | Mechanical power regeneration system |
US4936109A (en) | 1986-10-06 | 1990-06-26 | Columbia Energy Storage, Inc. | System and method for reducing gas compressor energy requirements |
US4765143A (en) | 1987-02-04 | 1988-08-23 | Cbi Research Corporation | Power plant using CO2 as a working fluid |
US4792700A (en) | 1987-04-14 | 1988-12-20 | Ammons Joe L | Wind driven electrical generating system |
US4870816A (en) | 1987-05-12 | 1989-10-03 | Gibbs & Hill, Inc. | Advanced recuperator |
US4765142A (en) | 1987-05-12 | 1988-08-23 | Gibbs & Hill, Inc. | Compressed air energy storage turbomachinery cycle with compression heat recovery, storage, steam generation and utilization during power generation |
US4885912A (en) | 1987-05-13 | 1989-12-12 | Gibbs & Hill, Inc. | Compressed air turbomachinery cycle with reheat and high pressure air preheating in recuperator |
US4872307A (en) | 1987-05-13 | 1989-10-10 | Gibbs & Hill, Inc. | Retrofit of simple cycle gas turbines for compressed air energy storage application |
FR2619203B1 (en) | 1987-08-04 | 1989-11-17 | Anhydride Carbonique Ind | CRYOGENIC COOLING PROCESS AND INSTALLATION USING LIQUID CARBON DIOXIDE AS A REFRIGERANT |
US4849648A (en) * | 1987-08-24 | 1989-07-18 | Columbia Energy Storage, Inc. | Compressed gas system and method |
US4876992A (en) | 1988-08-19 | 1989-10-31 | Standard Oil Company | Crankshaft phasing mechanism |
GB8821114D0 (en) | 1988-09-08 | 1988-10-05 | Turnbill W G | Electricity generating systems |
IL108559A (en) | 1988-09-19 | 1998-03-10 | Ormat | Method of and apparatus for producing power using compressed air |
US4942736A (en) | 1988-09-19 | 1990-07-24 | Ormat Inc. | Method of and apparatus for producing power from solar energy |
US4947977A (en) | 1988-11-25 | 1990-08-14 | Raymond William S | Apparatus for supplying electric current and compressed air |
GB2225616A (en) | 1988-11-30 | 1990-06-06 | Wind Energy Group Limited | Power generating system including gearing allowing constant generator torque |
US4955195A (en) | 1988-12-20 | 1990-09-11 | Stewart & Stevenson Services, Inc. | Fluid control circuit and method of operating pressure responsive equipment |
US4873831A (en) | 1989-03-27 | 1989-10-17 | Hughes Aircraft Company | Cryogenic refrigerator employing counterflow passageways |
US5209063A (en) | 1989-05-24 | 1993-05-11 | Kabushiki Kaisha Komatsu Seisakusho | Hydraulic circuit utilizing a compensator pressure selecting value |
US5062498A (en) | 1989-07-18 | 1991-11-05 | Jaromir Tobias | Hydrostatic power transfer system with isolating accumulator |
US5107681A (en) | 1990-08-10 | 1992-04-28 | Savair Inc. | Oleopneumatic intensifier cylinder |
US4984432A (en) | 1989-10-20 | 1991-01-15 | Corey John A | Ericsson cycle machine |
EP0429154B1 (en) | 1989-11-21 | 1994-12-21 | Mitsubishi Jukogyo Kabushiki Kaisha | Method for the fixation of carbon dioxide and apparatus for the treatment of carbon dioxide |
US5161449A (en) | 1989-12-22 | 1992-11-10 | The United States Of America As Represented By The Secretary Of The Navy | Pneumatic actuator with hydraulic control |
US5058385A (en) | 1989-12-22 | 1991-10-22 | The United States Of America As Represented By The Secretary Of The Navy | Pneumatic actuator with hydraulic control |
US5087824A (en) | 1990-04-09 | 1992-02-11 | Bill Nelson | Power plant for generation of electrical power and pneumatic pressure |
DE59100064D1 (en) | 1990-05-04 | 1993-04-29 | Wolfgang Barth | METHOD FOR DRIVING A PNEUMATIC MOTOR AND DEVICE FOR CARRYING OUT THE METHOD. |
US5271225A (en) | 1990-05-07 | 1993-12-21 | Alexander Adamides | Multiple mode operated motor with various sized orifice ports |
US5056601A (en) | 1990-06-21 | 1991-10-15 | Grimmer John E | Air compressor cooling system |
JP2818474B2 (en) | 1990-07-04 | 1998-10-30 | 日立建機株式会社 | Hydraulic drive circuit |
US5524821A (en) | 1990-12-20 | 1996-06-11 | Jetec Company | Method and apparatus for using a high-pressure fluid jet |
US5321946A (en) | 1991-01-25 | 1994-06-21 | Abdelmalek Fawzy T | Method and system for a condensing boiler and flue gas cleaning by cooling and liquefaction |
US5133190A (en) | 1991-01-25 | 1992-07-28 | Abdelmalek Fawzy T | Method and apparatus for flue gas cleaning by separation and liquefaction of sulfur dioxide and carbon dioxide |
DK23391D0 (en) | 1991-02-12 | 1991-02-12 | Soerensen Jens Richard | WINDOW FOR SELF-SUPPLY AND STORAGE OF ENERGY |
US5138838A (en) | 1991-02-15 | 1992-08-18 | Caterpillar Inc. | Hydraulic circuit and control system therefor |
US5152260A (en) | 1991-04-04 | 1992-10-06 | North American Philips Corporation | Highly efficient pneumatically powered hydraulically latched actuator |
US5365980A (en) | 1991-05-28 | 1994-11-22 | Instant Terminalling And Ship Conversion, Inc. | Transportable liquid products container |
EP0589960B1 (en) | 1991-06-17 | 1997-01-02 | Electric Power Research Institute, Inc | Power plant utilizing compressed air energy storage |
US5213470A (en) | 1991-08-16 | 1993-05-25 | Robert E. Lundquist | Wind turbine |
US5169295A (en) | 1991-09-17 | 1992-12-08 | Tren.Fuels, Inc. | Method and apparatus for compressing gases with a liquid system |
US5239833A (en) | 1991-10-07 | 1993-08-31 | Fineblum Engineering Corp. | Heat pump system and heat pump device using a constant flow reverse stirling cycle |
DE69228910T2 (en) | 1991-10-09 | 1999-09-23 | Kansai Electric Power Co | Recovery of carbon dioxide from combustion exhaust gas |
SK368091A3 (en) | 1991-12-04 | 1994-05-11 | Frantisek Krnavek | Device for potential energy recuperation of working device of building or earth machine |
JP2792777B2 (en) | 1992-01-17 | 1998-09-03 | 関西電力株式会社 | Method for removing carbon dioxide from flue gas |
GB2263734B (en) | 1992-01-31 | 1995-11-29 | Declan Nigel Pritchard | Smoothing electrical power output from means for generating electricity from wind |
US5327987A (en) | 1992-04-02 | 1994-07-12 | Abdelmalek Fawzy T | High efficiency hybrid car with gasoline engine, and electric battery powered motor |
US5259345A (en) | 1992-05-05 | 1993-11-09 | North American Philips Corporation | Pneumatically powered actuator with hydraulic latching |
US5309713A (en) | 1992-05-06 | 1994-05-10 | Vassallo Franklin A | Compressed gas engine and method of operating same |
GB2300673B (en) | 1992-05-29 | 1997-01-15 | Nat Power Plc | A gas turbine plant |
JP3504946B2 (en) | 1992-05-29 | 2004-03-08 | イノジーパブリックリミテッドカンパニー | Heat recovery device |
GB9211405D0 (en) | 1992-05-29 | 1992-07-15 | Nat Power Plc | A compressor for supplying compressed gas |
US5906108A (en) | 1992-06-12 | 1999-05-25 | Kidwell Environmental, Ltd., Inc. | Centrifugal heat transfer engine and heat transfer system embodying the same |
US6964176B2 (en) | 1992-06-12 | 2005-11-15 | Kelix Heat Transfer Systems, Llc | Centrifugal heat transfer engine and heat transfer systems embodying the same |
JP3281984B2 (en) | 1992-06-13 | 2002-05-13 | 日本テキサス・インスツルメンツ株式会社 | Substrate voltage generation circuit |
US5924283A (en) | 1992-06-25 | 1999-07-20 | Enmass, Inc. | Energy management and supply system and method |
US5279206A (en) | 1992-07-14 | 1994-01-18 | Eaton Corporation | Variable displacement hydrostatic device and neutral return mechanism therefor |
US5296799A (en) | 1992-09-29 | 1994-03-22 | Davis Emsley A | Electric power system |
US5937652A (en) | 1992-11-16 | 1999-08-17 | Abdelmalek; Fawzy T. | Process for coal or biomass fuel gasification by carbon dioxide extracted from a boiler flue gas stream |
GB9225103D0 (en) | 1992-12-01 | 1993-01-20 | Nat Power Plc | A heat engine and heat pump |
KR960007104B1 (en) | 1993-03-04 | 1996-05-27 | 조철승 | Engine using compressed air |
US5454408A (en) | 1993-08-11 | 1995-10-03 | Thermo Power Corporation | Variable-volume storage and dispensing apparatus for compressed natural gas |
US5454426A (en) | 1993-09-20 | 1995-10-03 | Moseley; Thomas S. | Thermal sweep insulation system for minimizing entropy increase of an associated adiabatic enthalpizer |
US5685155A (en) | 1993-12-09 | 1997-11-11 | Brown; Charles V. | Method for energy conversion |
US5562010A (en) | 1993-12-13 | 1996-10-08 | Mcguire; Bernard | Reversing drive |
JP3353259B2 (en) | 1994-01-25 | 2002-12-03 | 謙三 星野 | Turbin |
IL108546A (en) | 1994-02-03 | 1997-01-10 | Israel Electric Corp Ltd | Compressed air energy storage method and system |
US5427194A (en) | 1994-02-04 | 1995-06-27 | Miller; Edward L. | Electrohydraulic vehicle with battery flywheel |
US5384489A (en) | 1994-02-07 | 1995-01-24 | Bellac; Alphonse H. | Wind-powered electricity generating system including wind energy storage |
US5394693A (en) | 1994-02-25 | 1995-03-07 | Daniels Manufacturing Corporation | Pneumatic/hydraulic remote power unit |
US5544698A (en) | 1994-03-30 | 1996-08-13 | Peerless Of America, Incorporated | Differential coatings for microextruded tubes used in parallel flow heat exchangers |
US5674053A (en) | 1994-04-01 | 1997-10-07 | Paul; Marius A. | High pressure compressor with controlled cooling during the compression phase |
US5769610A (en) | 1994-04-01 | 1998-06-23 | Paul; Marius A. | High pressure compressor with internal, cooled compression |
US5584664A (en) | 1994-06-13 | 1996-12-17 | Elliott; Alvin B. | Hydraulic gas compressor and method for use |
US5711653A (en) | 1994-07-31 | 1998-01-27 | Mccabe; Francis J. | Air lifted airfoil |
US5467722A (en) | 1994-08-22 | 1995-11-21 | Meratla; Zoher M. | Method and apparatus for removing pollutants from flue gas |
US5600953A (en) | 1994-09-28 | 1997-02-11 | Aisin Seiki Kabushiki Kaisha | Compressed air control apparatus |
US5634340A (en) | 1994-10-14 | 1997-06-03 | Dresser Rand Company | Compressed gas energy storage system with cooling capability |
JP3009090B2 (en) | 1994-11-08 | 2000-02-14 | 信越化学工業株式会社 | Siloxane-containing pullulan and method for producing the same |
US5561978A (en) | 1994-11-17 | 1996-10-08 | Itt Automotive Electrical Systems, Inc. | Hydraulic motor system |
US5557934A (en) | 1994-12-20 | 1996-09-24 | Epoch Engineering, Inc. | Efficient energy conversion apparatus and method especially arranged to employ a stirling engine or alternately arranged to employ an internal combustion engine |
US5616007A (en) | 1994-12-21 | 1997-04-01 | Cohen; Eric L. | Liquid spray compressor |
US5579640A (en) | 1995-04-27 | 1996-12-03 | The United States Of America As Represented By The Administrator Of The Environmental Protection Agency | Accumulator engine |
US5607027A (en) | 1995-04-28 | 1997-03-04 | Anser, Inc. | Hydraulic drive system for a vehicle |
US5901809A (en) | 1995-05-08 | 1999-05-11 | Berkun; Andrew | Apparatus for supplying compressed air |
US5598736A (en) | 1995-05-19 | 1997-02-04 | N.A. Taylor Co. Inc. | Traction bending |
DE19530253A1 (en) * | 1995-05-23 | 1996-11-28 | Lothar Wanzke | Wind-powered energy generation plant |
US6170264B1 (en) | 1997-09-22 | 2001-01-09 | Clean Energy Systems, Inc. | Hydrocarbon combustion power generation system with CO2 sequestration |
US5634339A (en) | 1995-06-30 | 1997-06-03 | Ralph H. Lewis | Non-polluting, open brayton cycle automotive power unit |
US6132181A (en) | 1995-07-31 | 2000-10-17 | Mccabe; Francis J. | Windmill structures and systems |
US5599172A (en) | 1995-07-31 | 1997-02-04 | Mccabe; Francis J. | Wind energy conversion system |
JP3194047B2 (en) * | 1995-11-03 | 2001-07-30 | シフェリー,イヴァン | Air-oil converter for energy storage |
RU2101562C1 (en) | 1995-11-22 | 1998-01-10 | Василий Афанасьевич Палкин | Wind-electric storage plant |
JP2877098B2 (en) | 1995-12-28 | 1999-03-31 | 株式会社日立製作所 | Gas turbines, combined cycle plants and compressors |
FR2746667B1 (en) | 1996-03-27 | 1998-05-07 | Air Liquide | ATMOSPHERIC AIR TREATMENT METHOD AND INSTALLATION FOR A SEPARATION APPARATUS |
US5700311A (en) | 1996-04-30 | 1997-12-23 | Spencer; Dwain F. | Methods of selectively separating CO2 from a multicomponent gaseous stream |
US5971027A (en) * | 1996-07-01 | 1999-10-26 | Wisconsin Alumni Research Foundation | Accumulator for energy storage and delivery at multiple pressures |
US5831757A (en) | 1996-09-12 | 1998-11-03 | Pixar | Multiple cylinder deflection system |
GB9621405D0 (en) | 1996-10-14 | 1996-12-04 | Nat Power Plc | Apparatus for controlling gas temperature |
US5775107A (en) | 1996-10-21 | 1998-07-07 | Sparkman; Scott | Solar powered electrical generating system |
ATE477703T1 (en) | 1996-10-24 | 2010-08-15 | Ncon Corp Pty Ltd | POWER CONTROL DEVICE FOR LIGHTING SYSTEMS |
JP3574915B2 (en) | 1996-11-08 | 2004-10-06 | 同和鉱業株式会社 | Silver oxide for batteries, method for producing the same, and batteries using the same |
US5819533A (en) | 1996-12-19 | 1998-10-13 | Moonen; Raymond J. | Hydraulic-pneumatic motor |
US5839270A (en) | 1996-12-20 | 1998-11-24 | Jirnov; Olga | Sliding-blade rotary air-heat engine with isothermal compression of air |
US6419462B1 (en) | 1997-02-24 | 2002-07-16 | Ebara Corporation | Positive displacement type liquid-delivery apparatus |
US6023105A (en) | 1997-03-24 | 2000-02-08 | Youssef; Wasfi | Hybrid wind-hydro power plant |
JP3433415B2 (en) | 1997-04-21 | 2003-08-04 | アイダエンジニアリング株式会社 | Slide drive of press machine |
JP4285781B2 (en) | 1997-04-22 | 2009-06-24 | 株式会社日立製作所 | Gas turbine power generation equipment |
US5832728A (en) | 1997-04-29 | 1998-11-10 | Buck; Erik S. | Process for transmitting and storing energy |
JPH10313547A (en) * | 1997-05-09 | 1998-11-24 | Mitsubishi Heavy Ind Ltd | Hydraulic generator |
US6012279A (en) | 1997-06-02 | 2000-01-11 | General Electric Company | Gas turbine engine with water injection |
US5778675A (en) | 1997-06-20 | 1998-07-14 | Electric Power Research Institute, Inc. | Method of power generation and load management with hybrid mode of operation of a combustion turbine derivative power plant |
US6256976B1 (en) | 1997-06-27 | 2001-07-10 | Hitachi, Ltd. | Exhaust gas recirculation type combined plant |
SG104914A1 (en) | 1997-06-30 | 2004-07-30 | Hitachi Ltd | Gas turbine |
US6422016B2 (en) | 1997-07-03 | 2002-07-23 | Mohammed Alkhamis | Energy generating system using differential elevation |
KR100259845B1 (en) | 1997-08-22 | 2000-06-15 | 윤종용 | Grouping method between omni-cells pseudorandom-noise offset |
US6367570B1 (en) | 1997-10-17 | 2002-04-09 | Electromotive Inc. | Hybrid electric vehicle with electric motor providing strategic power assist to load balance internal combustion engine |
US6026349A (en) | 1997-11-06 | 2000-02-15 | Heneman; Helmuth J. | Energy storage and distribution system |
EP0924410B1 (en) | 1997-12-17 | 2003-09-24 | ALSTOM (Switzerland) Ltd | Method of operating a gas turbo group |
US5832906A (en) | 1998-01-06 | 1998-11-10 | Westport Research Inc. | Intensifier apparatus and method for supplying high pressure gaseous fuel to an internal combustion engine |
US5845479A (en) | 1998-01-20 | 1998-12-08 | Electric Power Research Institute, Inc. | Method for providing emergency reserve power using storage techniques for electrical systems applications |
US5975162A (en) | 1998-04-02 | 1999-11-02 | Link, Jr.; Clarence J. | Liquid delivery vehicle with remote control system |
JPH11324710A (en) | 1998-05-20 | 1999-11-26 | Hitachi Ltd | Gas turbine power plant |
US6349543B1 (en) | 1998-06-30 | 2002-02-26 | Robert Moshe Lisniansky | Regenerative adaptive fluid motor control |
US5934063A (en) | 1998-07-07 | 1999-08-10 | Nakhamkin; Michael | Method of operating a combustion turbine power plant having compressed air storage |
FR2781619B1 (en) | 1998-07-27 | 2000-10-13 | Guy Negre | COMPRESSED AIR BACKUP GENERATOR |
ATE263313T1 (en) | 1998-07-31 | 2004-04-15 | Texas A & M Univ Sys | NON-COLLECTIVE GEROTOR COMPRESSOR AND GEROTOR EXPANDER |
US6148602A (en) | 1998-08-12 | 2000-11-21 | Norther Research & Engineering Corporation | Solid-fueled power generation system with carbon dioxide sequestration and method therefor |
CN1061262C (en) | 1998-08-19 | 2001-01-31 | 刘毅刚 | Eye drops for treating conjunctivitis and preparing process thereof |
US6073448A (en) | 1998-08-27 | 2000-06-13 | Lozada; Vince M. | Method and apparatus for steam generation from isothermal geothermal reservoirs |
AUPP565098A0 (en) | 1998-09-03 | 1998-09-24 | Hbp Permo-Drive Pty Ltd | Energy management system |
US6170443B1 (en) | 1998-09-11 | 2001-01-09 | Edward Mayer Halimi | Internal combustion engine with a single crankshaft and having opposed cylinders with opposed pistons |
US6554088B2 (en) | 1998-09-14 | 2003-04-29 | Paice Corporation | Hybrid vehicles |
DE59810850D1 (en) | 1998-09-30 | 2004-04-01 | Alstom Technology Ltd Baden | Process for isothermal compression of air and nozzle arrangement for carrying out the process |
JP2000166128A (en) | 1998-11-24 | 2000-06-16 | Hideo Masubuchi | Energy storage system and its using method |
MY115510A (en) | 1998-12-18 | 2003-06-30 | Exxon Production Research Co | Method for displacing pressurized liquefied gas from containers |
US6158499A (en) | 1998-12-23 | 2000-12-12 | Fafco, Inc. | Method and apparatus for thermal energy storage |
US6029445A (en) | 1999-01-20 | 2000-02-29 | Case Corporation | Variable flow hydraulic system |
DE19903907A1 (en) | 1999-02-01 | 2000-08-03 | Mannesmann Rexroth Ag | Hydraulic load drive method, for a fork-lift truck , involves using free piston engine connected in parallel with pneumatic-hydraulic converter so load can be optionally driven by converter and/or engine |
DK1155225T3 (en) | 1999-02-24 | 2003-11-17 | Kema Nv | Combustion unit for combustion of a liquid fuel and a power generation system comprising such combustion unit |
US6153943A (en) | 1999-03-03 | 2000-11-28 | Mistr, Jr.; Alfred F. | Power conditioning apparatus with energy conversion and storage |
CA2365353A1 (en) | 1999-03-05 | 2000-09-14 | Kensuke Honma | Vane and piston type rotary machines |
DE19911534A1 (en) | 1999-03-16 | 2000-09-21 | Eckhard Wahl | Energy storage with compressed air for domestic and wind- power stations, using containers joined in parallel or having several compartments for storing compressed air |
US6179446B1 (en) | 1999-03-24 | 2001-01-30 | Eg&G Ilc Technology, Inc. | Arc lamp lightsource module |
US6073445A (en) | 1999-03-30 | 2000-06-13 | Johnson; Arthur | Methods for producing hydro-electric power |
EA002868B1 (en) | 1999-04-28 | 2002-10-31 | Коммонвелт Сайентифик Энд Индастриал Рисерч Организейшн | A thermodynamic apparatus |
JP2000346093A (en) | 1999-06-07 | 2000-12-12 | Nissan Diesel Motor Co Ltd | Clutch driving device for vehicle |
US6216462B1 (en) | 1999-07-19 | 2001-04-17 | The United States Of America As Represented By The Administrator Of The Environmental Protection Agency | High efficiency, air bottoming engine |
DE19933989A1 (en) | 1999-07-20 | 2001-01-25 | Linde Gas Ag | Method and compressor module for compressing a gas stream |
US6210131B1 (en) | 1999-07-28 | 2001-04-03 | The Regents Of The University Of California | Fluid intensifier having a double acting power chamber with interconnected signal rods |
US6372023B1 (en) | 1999-07-29 | 2002-04-16 | Secretary Of Agency Of Industrial Science And Technology | Method of separating and recovering carbon dioxide from combustion exhausted gas and apparatus therefor |
CA2578277C (en) | 1999-09-01 | 2009-10-20 | Ykk Corporation | Flexible container for liquid transport, liquid transport method using the container, liquid transport apparatus using the container, method for washing the container, and washingequipment |
US6407465B1 (en) | 1999-09-14 | 2002-06-18 | Ge Harris Railway Electronics Llc | Methods and system for generating electrical power from a pressurized fluid source |
DE10042020A1 (en) | 1999-09-15 | 2001-05-23 | Neuhaeuser Gmbh & Co | Wind-power installation for converting wind to power/energy, incorporates rotor blade and energy converter built as compressed-air motor for converting wind energy into other forms of energy |
US6670402B1 (en) | 1999-10-21 | 2003-12-30 | Aspen Aerogels, Inc. | Rapid aerogel production process |
US6815840B1 (en) | 1999-12-08 | 2004-11-09 | Metaz K. M. Aldendeshe | Hybrid electric power generator and method for generating electric power |
US6892802B2 (en) | 2000-02-09 | 2005-05-17 | Board Of Supervisors Of Louisiana State University And Agricultural And Mechanical College | Crossflow micro heat exchanger |
FR2805008B1 (en) | 2000-02-16 | 2002-05-31 | Joseph Haiun | TERMOCINETIC COMPRESSOR |
US6401458B2 (en) | 2000-02-28 | 2002-06-11 | Quoin International, Inc. | Pneumatic/mechanical actuator |
RU2169857C1 (en) | 2000-03-21 | 2001-06-27 | Новиков Михаил Иванович | Windmill plant |
US6352576B1 (en) | 2000-03-30 | 2002-03-05 | The Regents Of The University Of California | Methods of selectively separating CO2 from a multicomponent gaseous stream using CO2 hydrate promoters |
GB0007918D0 (en) | 2000-03-31 | 2000-05-17 | Npower | Passive valve assembly |
GB0007917D0 (en) | 2000-03-31 | 2000-05-17 | Npower | An engine |
GB0007925D0 (en) | 2000-03-31 | 2000-05-17 | Npower | A heat exchanger |
GB0007923D0 (en) | 2000-03-31 | 2000-05-17 | Npower | A two stroke internal combustion engine |
GB0007927D0 (en) | 2000-03-31 | 2000-05-17 | Npower | A gas compressor |
DE60119792T2 (en) | 2000-05-30 | 2007-05-10 | NHK Spring Co., Ltd., Yokohama | accumulator |
AUPQ785000A0 (en) | 2000-05-30 | 2000-06-22 | Commonwealth Scientific And Industrial Research Organisation | Heat engines and associated methods of producing mechanical energy and their application to vehicles |
DE10131805A1 (en) | 2000-07-29 | 2002-02-07 | Bosch Gmbh Robert | Pump unit for motor vehicle hydraulic brake unit, has end plugs in hollow rotor shaft to provide seat in which shaft is rotatably supported |
US6394559B1 (en) | 2000-09-15 | 2002-05-28 | Westinghouse Air Brake Technologies Corporation | Control apparatus for the application and release of a hand brake |
US6276123B1 (en) | 2000-09-21 | 2001-08-21 | Siemens Westinghouse Power Corporation | Two stage expansion and single stage combustion power plant |
DE60139273D1 (en) | 2000-09-25 | 2009-08-27 | Its Bus Inc | PLATFORMS FOR ENDURING TRANSPORT |
US6834737B2 (en) | 2000-10-02 | 2004-12-28 | Steven R. Bloxham | Hybrid vehicle and energy storage system and method |
CA2405812C (en) | 2000-10-10 | 2008-07-22 | American Electric Power Company, Inc. | A power load-leveling system and packet electrical storage |
US6360535B1 (en) | 2000-10-11 | 2002-03-26 | Ingersoll-Rand Company | System and method for recovering energy from an air compressor |
US20020068929A1 (en) | 2000-10-24 | 2002-06-06 | Roni Zvuloni | Apparatus and method for compressing a gas, and cryosurgery system and method utilizing same |
US6478289B1 (en) | 2000-11-06 | 2002-11-12 | General Electric Company | Apparatus and methods for controlling the supply of water mist to a gas-turbine compressor |
US6748737B2 (en) * | 2000-11-17 | 2004-06-15 | Patrick Alan Lafferty | Regenerative energy storage and conversion system |
FR2816993A1 (en) | 2000-11-21 | 2002-05-24 | Alvaro Martino | Energy storage and recovery system uses loop of circulating gas powered by injectors and driving output turbine |
MXPA03004752A (en) | 2000-11-28 | 2005-10-18 | Shep Ltd | Hydraulic energy storage systems. |
AUPR170400A0 (en) | 2000-11-28 | 2000-12-21 | Ifield Technology Ltd | Emergency energy release for hydraulic energy storage systems |
US20020084655A1 (en) | 2000-12-29 | 2002-07-04 | Abb Research Ltd. | System, method and computer program product for enhancing commercial value of electrical power produced from a renewable energy power production facility |
US20020112479A1 (en) | 2001-01-09 | 2002-08-22 | Keefer Bowie G. | Power plant with energy recovery from fuel storage |
US6619930B2 (en) | 2001-01-11 | 2003-09-16 | Mandus Group, Ltd. | Method and apparatus for pressurizing gas |
US6698472B2 (en) | 2001-02-02 | 2004-03-02 | Moc Products Company, Inc. | Housing for a fluid transfer machine and methods of use |
US6931848B2 (en) | 2001-03-05 | 2005-08-23 | Power Play Energy L.L.C. | Stirling engine having platelet heat exchanging elements |
US6513326B1 (en) | 2001-03-05 | 2003-02-04 | Joseph P. Maceda | Stirling engine having platelet heat exchanging elements |
US6516616B2 (en) | 2001-03-12 | 2003-02-11 | Pomfret Storage Comapny, Llc | Storage of energy producing fluids and process thereof |
GB2373546A (en) | 2001-03-19 | 2002-09-25 | Abb Offshore Systems Ltd | Apparatus for pressurising a hydraulic accumulator |
DE10116235A1 (en) | 2001-03-31 | 2002-10-17 | Hydac Technology Gmbh | Hydropneumatic pressure accumulator |
ATE276442T1 (en) | 2001-04-06 | 2004-10-15 | Sig Simonazzi Spa | HYDRAULIC PRESSURIZATION SYSTEM |
US6938415B2 (en) | 2001-04-10 | 2005-09-06 | Harry L. Last | Hydraulic/pneumatic apparatus |
US6739419B2 (en) | 2001-04-27 | 2004-05-25 | International Truck Intellectual Property Company, Llc | Vehicle engine cooling system without a fan |
US6711984B2 (en) | 2001-05-09 | 2004-03-30 | James E. Tagge | Bi-fluid actuator |
US20070245735A1 (en) | 2001-05-15 | 2007-10-25 | Daniel Ashikian | System and method for storing, disseminating, and utilizing energy in the form of gas compression and expansion including a thermo-dynamic battery |
DE10125350A1 (en) | 2001-05-23 | 2002-11-28 | Linde Ag | Device for cooling a component using a hydraulic fluid from a hydraulic circulation comprises a component positioned in a suction line connecting a tank to a pump and a control valve arranged between the component and the pump |
ES2179785B1 (en) | 2001-06-12 | 2006-10-16 | Ivan Lahuerta Antoune | SELF-MOLDING WIND TURBINE. |
WO2003019016A1 (en) | 2001-08-23 | 2003-03-06 | Neogas, Inc. | Method and apparatus for filling a storage vessel with compressed gas |
GB0121180D0 (en) | 2001-08-31 | 2001-10-24 | Innogy Plc | Compressor |
JP2003083230A (en) | 2001-09-14 | 2003-03-19 | Mitsubishi Heavy Ind Ltd | Wind mill power generation device, wind mill plant and operation method thereof |
FR2829805A1 (en) | 2001-09-14 | 2003-03-21 | Philippe Echevarria | Electrical energy production by compressed air pulse, wind driven generator has reserve of compressed air to drive wind turbine |
DE10147940A1 (en) | 2001-09-28 | 2003-05-22 | Siemens Ag | Operator panel for controlling motor vehicle systems, such as radio, navigation, etc., comprises a virtual display panel within the field of view of a camera, with detected finger positions used to activate a function |
CA2462852C (en) | 2001-10-05 | 2012-03-20 | Ben M. Enis | Method and apparatus for using wind turbines to generate and supply uninterrupted power to locations remote from the power grid |
US6963802B2 (en) | 2001-10-05 | 2005-11-08 | Enis Ben M | Method of coordinating and stabilizing the delivery of wind generated energy |
US7308361B2 (en) | 2001-10-05 | 2007-12-11 | Enis Ben M | Method of coordinating and stabilizing the delivery of wind generated energy |
US7504739B2 (en) | 2001-10-05 | 2009-03-17 | Enis Ben M | Method of transporting and storing wind generated energy using a pipeline |
US6606860B2 (en) | 2001-10-24 | 2003-08-19 | Mcfarland Rory S. | Energy conversion method and system with enhanced heat engine |
FR2831598A1 (en) | 2001-10-25 | 2003-05-02 | Mdi Motor Dev Internat | COMPRESSOR COMPRESSED AIR-INJECTION-MOTOR-GENERATOR MOTOR-GENERATOR GROUP OPERATING IN MONO AND PLURI ENERGIES |
US6516615B1 (en) | 2001-11-05 | 2003-02-11 | Ford Global Technologies, Inc. | Hydrogen engine apparatus with energy recovery |
DE20118183U1 (en) | 2001-11-08 | 2003-03-20 | Cvi Ind Mechthild Conrad E K | Power heat system for dwellings and vehicles, uses heat from air compression compressed air drives and wind and solar energy sources |
EP1310483B9 (en) | 2001-11-09 | 2006-07-05 | Samsung Electronics Co., Ltd. | Electrophotographic organophotoreceptors with charge transport compounds |
US6598392B2 (en) | 2001-12-03 | 2003-07-29 | William A. Majeres | Compressed gas engine with pistons and cylinders |
DE20120330U1 (en) | 2001-12-15 | 2003-04-24 | Cvi Ind Mechthild Conrad E K | Wind energy producing system has wind wheels inside a tower with wind being sucked in through inlet shafts over the wheels |
US20030145589A1 (en) | 2001-12-17 | 2003-08-07 | Tillyer Joseph P. | Fluid displacement method and apparatus |
US7055325B2 (en) | 2002-01-07 | 2006-06-06 | Wolken Myron B | Process and apparatus for generating power, producing fertilizer, and sequestering, carbon dioxide using renewable biomass |
US6745569B2 (en) | 2002-01-11 | 2004-06-08 | Alstom Technology Ltd | Power generation plant with compressed air energy system |
RU2213255C1 (en) | 2002-01-31 | 2003-09-27 | Сидоров Владимир Вячеславович | Method of and complex for conversion, accumulation and use of wind energy |
GB2385120B (en) | 2002-02-09 | 2004-05-19 | Thermetica Ltd | Thermal storage apparatus |
DE10205733B4 (en) | 2002-02-12 | 2005-11-10 | Peschke, Rudolf, Ing. | Apparatus for achieving isotherm-like compression or expansion of a gas |
DE10209880A1 (en) | 2002-03-06 | 2003-09-18 | Zf Lenksysteme Gmbh | System for controlling a hydraulic variable pump |
US7075189B2 (en) | 2002-03-08 | 2006-07-11 | Ocean Wind Energy Systems | Offshore wind turbine with multiple wind rotors and floating system |
WO2003076769A1 (en) | 2002-03-14 | 2003-09-18 | Alstom Technology Ltd | Thermal power process |
US7169489B2 (en) | 2002-03-15 | 2007-01-30 | Fuelsell Technologies, Inc. | Hydrogen storage, distribution, and recovery system |
US6938654B2 (en) | 2002-03-19 | 2005-09-06 | Air Products And Chemicals, Inc. | Monitoring of ultra-high purity product storage tanks during transportation |
US6848259B2 (en) | 2002-03-20 | 2005-02-01 | Alstom Technology Ltd | Compressed air energy storage system having a standby warm keeping system including an electric air heater |
DE10212480A1 (en) | 2002-03-21 | 2003-10-02 | Trupp Andreas | Heat pump method based on boiling point increase or vapor pressure reduction involves evaporating saturated vapor by isobaric/isothermal expansion, isobaric expansion, isobaric/isothermal compression |
FR2837530B1 (en) | 2002-03-21 | 2004-07-16 | Mdi Motor Dev Internat | INDIVIDUAL COGENERATION GROUP AND PROXIMITY NETWORK |
US6959546B2 (en) | 2002-04-12 | 2005-11-01 | Corcoran Craig C | Method and apparatus for energy generation utilizing temperature fluctuation-induced fluid pressure differentials |
FI118136B (en) | 2002-04-19 | 2007-07-13 | Marioff Corp Oy | Injection procedure and apparatus |
US6612348B1 (en) | 2002-04-24 | 2003-09-02 | Robert A. Wiley | Fluid delivery system for a road vehicle or water vessel |
JP3947423B2 (en) | 2002-04-26 | 2007-07-18 | 株式会社コーアガス日本 | Fast filling bulk lorry |
DE10220499A1 (en) | 2002-05-07 | 2004-04-15 | Bosch Maintenance Technologies Gmbh | Compressed air energy production method for commercial production of compressed air energy uses regenerative wind energy to be stored in underground air caverns beneath the North and Baltic Seas |
NZ537240A (en) | 2002-05-16 | 2007-06-29 | Mlh Global Corp Inc | Wind turbine with hydraulic transmission |
AU2003273532A1 (en) | 2002-06-04 | 2003-12-19 | Alstom Technology Ltd | Method for operating a compressor |
US7043907B2 (en) | 2002-07-11 | 2006-05-16 | Nabtesco Corporation | Electro-hydraulic actuation system |
CN1412443A (en) | 2002-08-07 | 2003-04-23 | 许忠 | Mechanical equipment capable of converting solar wind energy into air pressure energy and using said pressure energy to lift water |
ATE344154T1 (en) | 2002-08-09 | 2006-11-15 | Johann Jun Kerler | PNEUMATIC SUSPENSION AND HEIGHT ADJUSTMENT FOR VEHICLES |
GB0220685D0 (en) | 2002-09-05 | 2002-10-16 | Innogy Plc | A cylinder for an internal combustion engine |
US6715514B2 (en) | 2002-09-07 | 2004-04-06 | Worldwide Liquids | Method and apparatus for fluid transport, storage and dispensing |
US6666024B1 (en) | 2002-09-20 | 2003-12-23 | Daniel Moskal | Method and apparatus for generating energy using pressure from a large mass |
US6789387B2 (en) | 2002-10-01 | 2004-09-14 | Caterpillar Inc | System for recovering energy in hydraulic circuit |
US6960242B2 (en) | 2002-10-02 | 2005-11-01 | The Boc Group, Inc. | CO2 recovery process for supercritical extraction |
AU2003266613A1 (en) | 2002-10-10 | 2004-05-04 | Sony Corporation | Method of producing optical disk-use original and method of producing optical disk |
DE10248823A1 (en) | 2002-10-19 | 2004-05-06 | Hydac Technology Gmbh | hydraulic accumulator |
DE10249523C5 (en) | 2002-10-23 | 2015-12-24 | Minibooster Hydraulics A/S | booster |
US20040146408A1 (en) | 2002-11-14 | 2004-07-29 | Anderson Robert W. | Portable air compressor/tank device |
US7007474B1 (en) | 2002-12-04 | 2006-03-07 | The United States Of America As Represented By The United States Department Of Energy | Energy recovery during expansion of compressed gas using power plant low-quality heat sources |
DE10257951A1 (en) | 2002-12-12 | 2004-07-01 | Leybold Vakuum Gmbh | piston compressor |
US6739131B1 (en) | 2002-12-19 | 2004-05-25 | Charles H. Kershaw | Combustion-driven hydroelectric generating system with closed loop control |
US20060248886A1 (en) | 2002-12-24 | 2006-11-09 | Ma Thomas T H | Isothermal reciprocating machines |
WO2004059155A1 (en) | 2002-12-24 | 2004-07-15 | Thomas Tsoi-Hei Ma | Isothermal reciprocating machines |
US6797039B2 (en) | 2002-12-27 | 2004-09-28 | Dwain F. Spencer | Methods and systems for selectively separating CO2 from a multicomponent gaseous stream |
WO2004070211A1 (en) | 2003-01-14 | 2004-08-19 | Hitachi Construction Machinery Co., Ltd. | Hydraulic working machine |
WO2004067933A2 (en) | 2003-01-21 | 2004-08-12 | Los Angeles Advisory Services Inc. | Low emission energy source |
NL1022536C2 (en) | 2003-01-31 | 2004-08-04 | Seatools B V | System for storing, delivering and recovering energy. |
US7086231B2 (en) | 2003-02-05 | 2006-08-08 | Active Power, Inc. | Thermal and compressed air storage system |
US7127895B2 (en) | 2003-02-05 | 2006-10-31 | Active Power, Inc. | Systems and methods for providing backup energy to a load |
US7618606B2 (en) | 2003-02-06 | 2009-11-17 | The Ohio State University | Separation of carbon dioxide (CO2) from gas mixtures |
US6952058B2 (en) | 2003-02-20 | 2005-10-04 | Wecs, Inc. | Wind energy conversion system |
US6786245B1 (en) | 2003-02-21 | 2004-09-07 | Air Products And Chemicals, Inc. | Self-contained mobile fueling station |
TW200419606A (en) | 2003-03-24 | 2004-10-01 | Luxon Energy Devices Corp | Supercapacitor and a module of the same |
US6745801B1 (en) | 2003-03-25 | 2004-06-08 | Air Products And Chemicals, Inc. | Mobile hydrogen generation and supply system |
US20040211182A1 (en) | 2003-04-24 | 2004-10-28 | Gould Len Charles | Low cost heat engine which may be powered by heat from a phase change thermal storage material |
SE0301457L (en) | 2003-05-20 | 2004-11-21 | Cargine Engineering Ab | Method and device for pneumatic operation of a tool |
JP2007506039A (en) | 2003-05-30 | 2007-03-15 | エム. エニス,ベン | Method for storing and transporting energy generated by wind power using a pipeline system |
DE10325111A1 (en) | 2003-06-02 | 2005-01-05 | Alstom Technology Ltd | Method for generating energy in a gas turbine comprehensive power generation plant and power plant for performing the method |
US7453164B2 (en) | 2003-06-16 | 2008-11-18 | Polestar, Ltd. | Wind power system |
JP4121424B2 (en) | 2003-06-25 | 2008-07-23 | マスプロ電工株式会社 | Dual polarized antenna |
GB2403356A (en) | 2003-06-26 | 2004-12-29 | Hydrok | The use of a low voltage power source to operate a mechanical device to clean a screen in a combined sewer overflow system |
JP2005023918A (en) | 2003-07-01 | 2005-01-27 | Kenichi Kobayashi | Air storage type power generation |
JP4028826B2 (en) | 2003-07-18 | 2007-12-26 | 国男 宮崎 | Wind power generator |
DE10334637A1 (en) | 2003-07-29 | 2005-02-24 | Siemens Ag | Wind turbine has tower turbine rotor and electrical generator with compressed air energy storage system inside the tower and a feed to the mains |
US7028934B2 (en) | 2003-07-31 | 2006-04-18 | F. L. Smidth Inc. | Vertical roller mill with improved hydro-pneumatic loading system |
DE20312293U1 (en) | 2003-08-05 | 2003-12-18 | Löffler, Stephan | Supplying energy network for house has air compressor and distribution of compressed air to appliances with air driven motors |
DE10337601A1 (en) | 2003-08-16 | 2005-03-10 | Deere & Co | Hydropneumatic suspension device |
KR100411373B1 (en) | 2003-08-22 | 2003-12-18 | Dalim Won Co Ltd | Anti-sweating stone ossuary tomb having double foundations and triple walls |
US6922991B2 (en) | 2003-08-27 | 2005-08-02 | Moog Inc. | Regulated pressure supply for a variable-displacement reversible hydraulic motor |
WO2005027302A1 (en) | 2003-09-12 | 2005-03-24 | Alstom Technology Ltd | Modular power plant with a compressor and turbine unit and pressure storage volumes |
US20060175337A1 (en) | 2003-09-30 | 2006-08-10 | Defosset Josh P | Complex-shape compressed gas reservoirs |
WO2005041326A2 (en) | 2003-10-27 | 2005-05-06 | Ben M Enis | Storing and using energy to reduce the end-user cost |
US7124605B2 (en) | 2003-10-30 | 2006-10-24 | National Tank Company | Membrane/distillation method and system for extracting CO2 from hydrocarbon gas |
US7197871B2 (en) | 2003-11-14 | 2007-04-03 | Caterpillar Inc | Power system and work machine using same |
FR2862349B1 (en) | 2003-11-17 | 2006-02-17 | Mdi Motor Dev Internat Sa | ACTIVE MONO AND / OR ENERGY-STAR ENGINE WITH COMPRESSED AIR AND / OR ADDITIONAL ENERGY AND ITS THERMODYNAMIC CYCLE |
UA69030A (en) | 2003-11-27 | 2004-08-16 | Inst Of Hydro Mechanics Of The | Wind-power accumulating apparatus |
US6925821B2 (en) | 2003-12-02 | 2005-08-09 | Carrier Corporation | Method for extracting carbon dioxide for use as a refrigerant in a vapor compression system |
US6946017B2 (en) | 2003-12-04 | 2005-09-20 | Gas Technology Institute | Process for separating carbon dioxide and methane |
US20050279292A1 (en) | 2003-12-16 | 2005-12-22 | Hudson Robert S | Methods and systems for heating thermal storage units |
US7040108B1 (en) | 2003-12-16 | 2006-05-09 | Flammang Kevin E | Ambient thermal energy recovery system |
US6955050B2 (en) | 2003-12-16 | 2005-10-18 | Active Power, Inc. | Thermal storage unit and methods for using the same to heat a fluid |
US20050135934A1 (en) | 2003-12-22 | 2005-06-23 | Mechanology, Llc | Use of intersecting vane machines in combination with wind turbines |
SE526379C2 (en) | 2004-01-22 | 2005-09-06 | Cargine Engineering Ab | Method and system for controlling a device for compression |
US7040859B2 (en) | 2004-02-03 | 2006-05-09 | Vic Kane | Wind turbine |
US6922997B1 (en) | 2004-02-03 | 2005-08-02 | International Truck Intellectual Property Company, Llc | Engine based kinetic energy recovery system for vehicles |
TW200526871A (en) | 2004-02-15 | 2005-08-16 | Dah-Shan Lin | Pressure storage structure used in air |
US7050900B2 (en) | 2004-02-17 | 2006-05-23 | Miller Kenneth C | Dynamically reconfigurable internal combustion engine |
US7168928B1 (en) | 2004-02-17 | 2007-01-30 | Wilden Pump And Engineering Llc | Air driven hydraulic pump |
WO2005079461A2 (en) | 2004-02-17 | 2005-09-01 | Pneuvolt, Inc. | Vehicle system to recapture kinetic energy |
US7178353B2 (en) | 2004-02-19 | 2007-02-20 | Advanced Thermal Sciences Corp. | Thermal control system and method |
GB2411209A (en) | 2004-02-20 | 2005-08-24 | Rolls Royce Plc | Wind-driven power generating apparatus |
US6964165B2 (en) | 2004-02-27 | 2005-11-15 | Uhl Donald A | System and process for recovering energy from a compressed gas |
DK200400409A (en) | 2004-03-12 | 2004-04-21 | Neg Micon As | Variable capacity oil pump |
WO2005095155A1 (en) | 2004-03-30 | 2005-10-13 | Russell Glentworth Fletcher | Liquid transport vessel |
ATE508772T1 (en) | 2004-04-05 | 2011-05-15 | Mine Safety Appliances Co | DEVICE FOR GENERATING ELECTRICITY FROM GASES STORED IN PRESSURIZED CONTAINERS |
US7231998B1 (en) | 2004-04-09 | 2007-06-19 | Michael Moses Schechter | Operating a vehicle with braking energy recovery |
US7325401B1 (en) | 2004-04-13 | 2008-02-05 | Brayton Energy, Llc | Power conversion systems |
DE102004018456A1 (en) | 2004-04-16 | 2005-11-10 | Hydac Technology Gmbh | hydraulic accumulator |
US7481337B2 (en) | 2004-04-26 | 2009-01-27 | Georgia Tech Research Corporation | Apparatus for fluid storage and delivery at a substantially constant pressure |
GR1004955B (en) | 2004-04-27 | 2005-07-28 | Device converting thermal energy into kinetic one via a spontaneous isothermal gas aggregation | |
US7084520B2 (en) | 2004-05-03 | 2006-08-01 | Aerovironment, Inc. | Wind turbine system |
US7699909B2 (en) | 2004-05-04 | 2010-04-20 | The Trustees Of Columbia University In The City Of New York | Systems and methods for extraction of carbon dioxide from air |
US20070137595A1 (en) | 2004-05-13 | 2007-06-21 | Greenwell Gary A | Radial engine power system |
US7140182B2 (en) | 2004-06-14 | 2006-11-28 | Edward Lawrence Warren | Energy storing engine |
US7719127B2 (en) | 2004-06-15 | 2010-05-18 | Hamilton Sundstrand | Wind power system for energy production |
US7128777B2 (en) | 2004-06-15 | 2006-10-31 | Spencer Dwain F | Methods and systems for selectively separating CO2 from a multicomponent gaseous stream to produce a high pressure CO2 product |
US7488159B2 (en) | 2004-06-25 | 2009-02-10 | Air Products And Chemicals, Inc. | Zero-clearance ultra-high-pressure gas compressor |
US20090145130A1 (en) | 2004-08-20 | 2009-06-11 | Jay Stephen Kaufman | Building energy recovery, storage and supply system |
JP2008510933A (en) | 2004-08-24 | 2008-04-10 | インフィニア コーポレイション | Double-acting thermodynamic resonance-free piston multi-cylinder Stirling system and method |
US20060055175A1 (en) | 2004-09-14 | 2006-03-16 | Grinblat Zinovy D | Hybrid thermodynamic cycle and hybrid energy system |
US7047744B1 (en) | 2004-09-16 | 2006-05-23 | Robertson Stuart J | Dynamic heat sink engine |
US20060059912A1 (en) | 2004-09-17 | 2006-03-23 | Pat Romanelli | Vapor pump power system |
EP1637733A1 (en) | 2004-09-17 | 2006-03-22 | Elsam A/S | A power plant, a windmill, and a method of producing electrical power from wind energy |
US20060059937A1 (en) | 2004-09-17 | 2006-03-23 | Perkins David E | Systems and methods for providing cooling in compressed air storage power supply systems |
US20060059936A1 (en) | 2004-09-17 | 2006-03-23 | Radke Robert E | Systems and methods for providing cooling in compressed air storage power supply systems |
US7471010B1 (en) | 2004-09-29 | 2008-12-30 | Alliance For Sustainable Energy, Llc | Wind turbine tower for storing hydrogen and energy |
US7254944B1 (en) | 2004-09-29 | 2007-08-14 | Ventoso Systems, Llc | Energy storage system |
US7273122B2 (en) | 2004-09-30 | 2007-09-25 | Bosch Rexroth Corporation | Hybrid hydraulic drive system with engine integrated hydraulic machine |
US7124576B2 (en) | 2004-10-11 | 2006-10-24 | Deere & Company | Hydraulic energy intensifier |
JP5634658B2 (en) | 2004-10-15 | 2014-12-03 | クライマックス・モリブデナム・カンパニー | Apparatus and method for forming a gaseous fluid product |
US7347049B2 (en) | 2004-10-19 | 2008-03-25 | General Electric Company | Method and system for thermochemical heat energy storage and recovery |
US7249617B2 (en) | 2004-10-20 | 2007-07-31 | Musselman Brett A | Vehicle mounted compressed air distribution system |
US7284372B2 (en) | 2004-11-04 | 2007-10-23 | Darby Crow | Method and apparatus for converting thermal energy to mechanical energy |
US7527483B1 (en) | 2004-11-18 | 2009-05-05 | Carl J Glauber | Expansible chamber pneumatic system |
US7693402B2 (en) | 2004-11-19 | 2010-04-06 | Active Power, Inc. | Thermal storage unit and methods for using the same to heat a fluid |
US7841432B2 (en) | 2004-11-22 | 2010-11-30 | Bosch Rexroth Corporation | Hydro-electric hybrid drive system for motor vehicle |
US7093626B2 (en) | 2004-12-06 | 2006-08-22 | Ovonic Hydrogen Systems, Llc | Mobile hydrogen delivery system |
US20060201148A1 (en) | 2004-12-07 | 2006-09-14 | Zabtcioglu Fikret M | Hydraulic-compression power cogeneration system and method |
US7178337B2 (en) | 2004-12-23 | 2007-02-20 | Tassilo Pflanz | Power plant system for utilizing the heat energy of geothermal reservoirs |
US20060162910A1 (en) | 2005-01-24 | 2006-07-27 | International Mezzo Technologies, Inc. | Heat exchanger assembly |
CN1818377B (en) | 2005-02-13 | 2010-04-14 | 王瑛 | Wind-power apparatus, its energy-storing and wind-power generating |
JP4759282B2 (en) | 2005-02-14 | 2011-08-31 | 中村工機株式会社 | Two-stage pressure absorption piston type accumulator |
JP4497015B2 (en) | 2005-04-01 | 2010-07-07 | トヨタ自動車株式会社 | Thermal energy recovery device |
SE531220C2 (en) | 2005-04-21 | 2009-01-20 | Compower Ab | Energy recovery system for a process device |
US7690202B2 (en) | 2005-05-16 | 2010-04-06 | General Electric Company | Mobile gas turbine engine and generator assembly |
US7836714B2 (en) | 2005-05-27 | 2010-11-23 | Ingersoll-Rand Company | Thermal storage tank/base |
KR100638223B1 (en) | 2005-06-16 | 2006-10-27 | 엘지전자 주식회사 | Electric generation air condition system |
JP2007001872A (en) | 2005-06-21 | 2007-01-11 | Koei Kogyo Kk | alpha-GLUCOSIDASE INHIBITOR |
WO2007002094A2 (en) | 2005-06-21 | 2007-01-04 | Mechanology, Inc. | Serving end use customers with onsite compressed air energy storage systems |
CN1884822A (en) | 2005-06-23 | 2006-12-27 | 张建明 | Wind power generation technology employing telescopic sleeve cylinder to store wind energy |
CN2821162Y (en) | 2005-06-24 | 2006-09-27 | 周国君 | Cylindrical pneumatic engine |
CN1888328A (en) | 2005-06-28 | 2007-01-03 | 天津市海恩海洋工程技术服务有限公司 | Water hammer for pile driving |
GB2428038B (en) | 2005-07-06 | 2011-04-06 | Statoil Asa | Carbon dioxide extraction process |
US7266940B2 (en) | 2005-07-08 | 2007-09-11 | General Electric Company | Systems and methods for power generation with carbon dioxide isolation |
US8099198B2 (en) | 2005-07-25 | 2012-01-17 | Echogen Power Systems, Inc. | Hybrid power generation and energy storage system |
US7183664B2 (en) | 2005-07-27 | 2007-02-27 | Mcclintic Frank | Methods and apparatus for advanced wind turbine design |
US7364610B2 (en) * | 2005-07-28 | 2008-04-29 | Michael D. Falcon | Air filter sensor |
WO2007012143A1 (en) | 2005-07-29 | 2007-02-01 | Commonwealth Scientific And Industrial Research Organisation | Recovery of carbon dioxide from flue gases |
US7415995B2 (en) | 2005-08-11 | 2008-08-26 | Scott Technologies | Method and system for independently filling multiple canisters from cascaded storage stations |
US7841205B2 (en) | 2005-08-15 | 2010-11-30 | Whitemoss, Inc. | Integrated compressor/expansion engine |
US7329099B2 (en) | 2005-08-23 | 2008-02-12 | Paul Harvey Hartman | Wind turbine and energy distribution system |
WO2007023094A1 (en) | 2005-08-23 | 2007-03-01 | Alstom Technology Ltd | Power plant |
US7401475B2 (en) | 2005-08-24 | 2008-07-22 | Purdue Research Foundation | Thermodynamic systems operating with near-isothermal compression and expansion cycles |
CN2828319Y (en) | 2005-09-01 | 2006-10-18 | 罗勇 | High pressure pneumatic engine |
WO2007035997A1 (en) | 2005-09-28 | 2007-04-05 | Permo-Drive Research And Development Pty Ltd | Hydraulic circuit for a energy regenerative drive system |
CN2828368Y (en) | 2005-09-29 | 2006-10-18 | 何文良 | Wind power generating field set driven by wind compressed air |
CN1743665A (en) | 2005-09-29 | 2006-03-08 | 徐众勤 | Wind-power compressed air driven wind-mill generating field set |
DE102005047622A1 (en) | 2005-10-05 | 2007-04-12 | Prikot, Alexander, Dipl.-Ing. | Wind turbine electrical generator sets are powered by stored compressed air obtained under storm conditions |
NL1030313C2 (en) | 2005-10-31 | 2007-05-03 | Transp Industry Dev Ct Bv | Suspension system for a vehicle. |
US20070095069A1 (en) | 2005-11-03 | 2007-05-03 | General Electric Company | Power generation systems and method of operating same |
US7230348B2 (en) | 2005-11-04 | 2007-06-12 | Poole A Bruce | Infuser augmented vertical wind turbine electrical generating system |
CN1967091A (en) | 2005-11-18 | 2007-05-23 | 田振国 | Wind-energy compressor using wind energy to compress air |
US7488155B2 (en) | 2005-11-18 | 2009-02-10 | General Electric Company | Method and apparatus for wind turbine braking |
JP4421549B2 (en) | 2005-11-29 | 2010-02-24 | アイシン・エィ・ダブリュ株式会社 | Driving assistance device |
US8030793B2 (en) | 2005-12-07 | 2011-10-04 | The University Of Nottingham | Power generation |
US7485977B2 (en) | 2006-01-06 | 2009-02-03 | Aerodyne Research, Inc. | Power generating system |
US7353786B2 (en) | 2006-01-07 | 2008-04-08 | Scuderi Group, Llc | Split-cycle air hybrid engine |
US9127895B2 (en) | 2006-01-23 | 2015-09-08 | MAHLE Behr GmbH & Co. KG | Heat exchanger |
SE531872C2 (en) | 2006-01-24 | 2009-09-01 | Bengt H Nilsson Med Ultirec Fa | Procedure for incremental energy conversion |
US8733429B2 (en) | 2006-02-13 | 2014-05-27 | The H.L. Turner Group, Inc. | Hybrid heating and/or cooling system |
DE102006007743B4 (en) | 2006-02-20 | 2016-03-17 | Knorr-Bremse Systeme für Nutzfahrzeuge GmbH | Reciprocating compressor with non-contact gap seal |
EP1989400B2 (en) | 2006-02-27 | 2023-06-28 | Highview Enterprises Limited | A method of storing energy and a cryogenic energy storage system |
US7607503B1 (en) | 2006-03-03 | 2009-10-27 | Michael Moses Schechter | Operating a vehicle with high fuel efficiency |
US7856843B2 (en) | 2006-04-05 | 2010-12-28 | Enis Ben M | Thermal energy storage system using compressed air energy and/or chilled water from desalination processes |
US20070243066A1 (en) | 2006-04-17 | 2007-10-18 | Richard Baron | Vertical axis wind turbine |
US20070258834A1 (en) | 2006-05-04 | 2007-11-08 | Walt Froloff | Compressed gas management system |
US7417331B2 (en) | 2006-05-08 | 2008-08-26 | Towertech Research Group, Inc. | Combustion engine driven electric generator apparatus |
US20080050234A1 (en) * | 2006-05-19 | 2008-02-28 | General Compression, Inc. | Wind turbine system |
WO2007140261A2 (en) | 2006-05-24 | 2007-12-06 | Jupiter Oxygen Corporation | Integrated capture of fossil fuel gas pollutants including co2 with energy recovery |
DE102006042390A1 (en) * | 2006-06-02 | 2007-12-06 | Brueninghaus Hydromatik Gmbh | Drive with energy storage device and method for storing kinetic energy |
US7353845B2 (en) | 2006-06-08 | 2008-04-08 | Smith International, Inc. | Inline bladder-type accumulator for downhole applications |
US20090294096A1 (en) | 2006-07-14 | 2009-12-03 | Solar Heat And Power Pty Limited | Thermal energy storage system |
DE102006035273B4 (en) | 2006-07-31 | 2010-03-04 | Siegfried Dr. Westmeier | Process for effective and low-emission operation of power plants, as well as for energy storage and energy conversion |
US8544275B2 (en) | 2006-08-01 | 2013-10-01 | Research Foundation Of The City University Of New York | Apparatus and method for storing heat energy |
JP2008038658A (en) | 2006-08-02 | 2008-02-21 | Press Kogyo Co Ltd | Gas compressor |
KR100792790B1 (en) | 2006-08-21 | 2008-01-10 | 한국기계연구원 | Compressed air energy storage generation system and power generation method using it |
US7281371B1 (en) | 2006-08-23 | 2007-10-16 | Ebo Group, Inc. | Compressed air pumped hydro energy storage and distribution system |
US20080047272A1 (en) | 2006-08-28 | 2008-02-28 | Harry Schoell | Heat regenerative mini-turbine generator |
FR2905404B1 (en) | 2006-09-05 | 2012-11-23 | Mdi Motor Dev Internat Sa | ACTIVE MONO AND / OR ENERGY CHAMBER MOTOR WITH COMPRESSED AIR AND / OR ADDITIONAL ENERGY. |
CA2700209A1 (en) | 2006-09-22 | 2008-03-27 | Mechanology, Inc. | Oscillating vane machine with improved vane and valve actuation |
WO2008042919A2 (en) | 2006-10-02 | 2008-04-10 | Global Research Technologies, Llc | Method and apparatus for extracting carbon dioxide from air |
US8413436B2 (en) | 2006-10-10 | 2013-04-09 | Regents Of The University Of Minnesota | Open accumulator for compact liquid power energy storage |
CN101162073A (en) | 2006-10-15 | 2008-04-16 | 邸慧民 | Method for preparing compressed air by pneumatic air compressor |
US20080112807A1 (en) | 2006-10-23 | 2008-05-15 | Ulrich Uphues | Methods and apparatus for operating a wind turbine |
US7895822B2 (en) | 2006-11-07 | 2011-03-01 | General Electric Company | Systems and methods for power generation with carbon dioxide isolation |
US7843076B2 (en) * | 2006-11-29 | 2010-11-30 | Yshape Inc. | Hydraulic energy accumulator |
US20080127632A1 (en) | 2006-11-30 | 2008-06-05 | General Electric Company | Carbon dioxide capture systems and methods |
US20080157537A1 (en) | 2006-12-13 | 2008-07-03 | Richard Danny J | Hydraulic pneumatic power pumps and station |
WO2008074075A1 (en) | 2006-12-21 | 2008-06-26 | Mosaic Technologies Pty Ltd | A compressed gas transfer system |
US20080155975A1 (en) | 2006-12-28 | 2008-07-03 | Caterpillar Inc. | Hydraulic system with energy recovery |
US20080155976A1 (en) | 2006-12-28 | 2008-07-03 | Caterpillar Inc. | Hydraulic motor |
US20080164449A1 (en) | 2007-01-09 | 2008-07-10 | Gray Joseph L | Passive restraint for prevention of uncontrolled motion |
ITCH20070002A1 (en) | 2007-01-10 | 2008-07-11 | Leonardo Galloppa | SYSTEM FOR THE GENERATION OF ELECTRICITY FROM THE MARINE WAVE MOTORCYCLE |
US7640745B2 (en) | 2007-01-15 | 2010-01-05 | Concepts Eti, Inc. | High-pressure fluid compression system utilizing cascading effluent energy recovery |
US20080178601A1 (en) | 2007-01-25 | 2008-07-31 | Michael Nakhamkin | Power augmentation of combustion turbines with compressed air energy storage and additional expander with airflow extraction and injection thereof upstream of combustors |
US20080185194A1 (en) | 2007-02-02 | 2008-08-07 | Ford Global Technologies, Llc | Hybrid Vehicle With Engine Power Cylinder Deactivation |
DK176721B1 (en) | 2007-03-06 | 2009-04-27 | I/S Boewind V/Chr. I S Boewind V Chr | Procedure for the accumulation and utilization of renewable energy |
US7954321B2 (en) | 2007-03-08 | 2011-06-07 | Research Foundation Of The City University Of New York | Solar power plant and method and/or system of storing energy in a concentrated solar power plant |
CN101033731A (en) | 2007-03-09 | 2007-09-12 | 中国科学院电工研究所 | Wind-power pumping water generating system |
WO2008110018A1 (en) | 2007-03-12 | 2008-09-18 | Whalepower Corporation | Wind powered system for the direct mechanical powering of systems and energy storage devices |
US7831352B2 (en) | 2007-03-16 | 2010-11-09 | The Hartfiel Company | Hydraulic actuator control system |
US20080238187A1 (en) | 2007-03-30 | 2008-10-02 | Stephen Carl Garnett | Hydrostatic drive system with variable charge pump |
US8067852B2 (en) | 2007-03-31 | 2011-11-29 | Mdl Enterprises, Llc | Fluid driven electric power generation system |
WO2008121378A1 (en) | 2007-03-31 | 2008-10-09 | Mdl Enterprises, Llc | Wind-driven electric power generation system |
CN201103518Y (en) | 2007-04-04 | 2008-08-20 | 魏永彬 | Power generation device of pneumatic air compressor |
US7877999B2 (en) | 2007-04-13 | 2011-02-01 | Cool Energy, Inc. | Power generation and space conditioning using a thermodynamic engine driven through environmental heating and cooling |
CN101289963A (en) | 2007-04-18 | 2008-10-22 | 中国科学院工程热物理研究所 | Compressed-air energy-storage system |
CN101042115A (en) | 2007-04-30 | 2007-09-26 | 吴江市方霞企业信息咨询有限公司 | Storage tower of wind power generator |
WO2008153591A1 (en) | 2007-06-08 | 2008-12-18 | Omar De La Rosa | Omar vectorial energy conversion system |
JP2010530049A (en) | 2007-06-14 | 2010-09-02 | リモ−ライド インコーポレイテッド | Compact hydraulic accumulator |
CN101070822A (en) | 2007-06-15 | 2007-11-14 | 吴江市方霞企业信息咨询有限公司 | Tower-pressure type wind power generator |
US7870899B2 (en) | 2007-06-18 | 2011-01-18 | Conocophillips Company | Method for utilizing pressure variations as an energy source |
WO2008154752A1 (en) | 2007-06-21 | 2008-12-24 | Raymond Deshaies | Hybrid electric propulsion system |
US7634911B2 (en) | 2007-06-29 | 2009-12-22 | Caterpillar Inc. | Energy recovery system |
US7677036B2 (en) | 2007-07-02 | 2010-03-16 | Hall David R | Hydraulic energy storage with an internal element |
US7600376B2 (en) | 2007-07-02 | 2009-10-13 | Hall David R | Energy storage |
EP2014364A1 (en) | 2007-07-04 | 2009-01-14 | Technische Fachhochschule Wildau | Device and method for transferring linear movements |
US20090021012A1 (en) * | 2007-07-20 | 2009-01-22 | Stull Mark A | Integrated wind-power electrical generation and compressed air energy storage system |
US7975485B2 (en) | 2007-08-29 | 2011-07-12 | Yuanping Zhao | High efficiency integrated heat engine (HEIHE) |
WO2009034421A1 (en) | 2007-09-13 | 2009-03-19 | Ecole polytechnique fédérale de Lausanne (EPFL) | A multistage hydro-pneumatic motor-compressor |
US20090071155A1 (en) | 2007-09-14 | 2009-03-19 | General Electric Company | Method and system for thermochemical heat energy storage and recovery |
NO20075029L (en) | 2007-10-05 | 2009-04-06 | Multicontrol Hydraulics As | Electrically operated hydraulic pump unit with accumulator module for use in underwater control systems. |
CN201106527Y (en) | 2007-10-19 | 2008-08-27 | 席明强 | Wind energy air compression power device |
EP2052889B1 (en) | 2007-10-26 | 2016-06-15 | Strömsholmen AB | Hydropneumatic spring-damping device and method of operation of a hydropneumatic spring-damping device |
CN100519998C (en) | 2007-11-02 | 2009-07-29 | 浙江大学 | Compressed air engine electrically driven whole-variable valve actuating system |
US8156725B2 (en) | 2007-12-21 | 2012-04-17 | Palo Alto Research Center Incorporated | CO2 capture during compressed air energy storage |
US7827787B2 (en) | 2007-12-27 | 2010-11-09 | Deere & Company | Hydraulic system |
US7938217B2 (en) | 2008-03-11 | 2011-05-10 | Physics Lab Of Lake Havasu, Llc | Regenerative suspension with accumulator systems and methods |
US8250863B2 (en) | 2008-04-09 | 2012-08-28 | Sustainx, Inc. | Heat exchange with compressed gas in energy-storage systems |
US8677744B2 (en) | 2008-04-09 | 2014-03-25 | SustaioX, Inc. | Fluid circulation in energy storage and recovery systems |
US8037678B2 (en) | 2009-09-11 | 2011-10-18 | Sustainx, Inc. | Energy storage and generation systems and methods using coupled cylinder assemblies |
US7958731B2 (en) | 2009-01-20 | 2011-06-14 | Sustainx, Inc. | Systems and methods for combined thermal and compressed gas energy conversion systems |
US20100307156A1 (en) | 2009-06-04 | 2010-12-09 | Bollinger Benjamin R | Systems and Methods for Improving Drivetrain Efficiency for Compressed Gas Energy Storage and Recovery Systems |
US8448433B2 (en) | 2008-04-09 | 2013-05-28 | Sustainx, Inc. | Systems and methods for energy storage and recovery using gas expansion and compression |
WO2009126784A2 (en) * | 2008-04-09 | 2009-10-15 | Sustainx, Inc. | Systems and methods for energy storage and recovery using compressed gas |
US8225606B2 (en) | 2008-04-09 | 2012-07-24 | Sustainx, Inc. | Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression |
US7802426B2 (en) | 2008-06-09 | 2010-09-28 | Sustainx, Inc. | System and method for rapid isothermal gas expansion and compression for energy storage |
US8359856B2 (en) | 2008-04-09 | 2013-01-29 | Sustainx Inc. | Systems and methods for efficient pumping of high-pressure fluids for energy storage and recovery |
US8479505B2 (en) | 2008-04-09 | 2013-07-09 | Sustainx, Inc. | Systems and methods for reducing dead volume in compressed-gas energy storage systems |
US8240140B2 (en) | 2008-04-09 | 2012-08-14 | Sustainx, Inc. | High-efficiency energy-conversion based on fluid expansion and compression |
US7579700B1 (en) | 2008-05-28 | 2009-08-25 | Moshe Meller | System and method for converting electrical energy into pressurized air and converting pressurized air into electricity |
GB2461061A (en) | 2008-06-19 | 2009-12-23 | Vetco Gray Controls Ltd | Subsea hydraulic intensifier with supply directional control valves electronically switched |
EP3002422B1 (en) | 2008-06-25 | 2020-02-19 | Siemens Aktiengesellschaft | Energy storage system and method for storing and supplying energy |
US20100032909A1 (en) * | 2008-08-06 | 2010-02-11 | Ford Global Technologies Llc | Engine Cylinder Head Gasket Assembly |
US20100032903A1 (en) * | 2008-08-07 | 2010-02-11 | Ling-Wan Wang | Board game with scissors, rock, and paper pieces which are faced down at the start of game |
CN101377190A (en) | 2008-09-25 | 2009-03-04 | 朱仕亮 | Apparatus for collecting compressed air by ambient pressure |
FI125918B (en) | 2008-10-10 | 2016-04-15 | Norrhydro Oy | Pressure medium system for load control, turning device for controlling the rotational movement of the load and eccentric turning device for controlling the rotation of the load |
CN101408213A (en) | 2008-11-11 | 2009-04-15 | 浙江大学 | Energy recovery system of hybrid power engineering machinery energy accumulator-hydraulic motor |
CN101435451B (en) | 2008-12-09 | 2012-03-28 | 中南大学 | Movable arm potential energy recovery method and apparatus of hydraulic excavator |
US7963110B2 (en) | 2009-03-12 | 2011-06-21 | Sustainx, Inc. | Systems and methods for improving drivetrain efficiency for compressed gas energy storage |
CA2762980A1 (en) | 2009-05-22 | 2010-11-25 | General Compression Inc. | Compressor and/or expander device |
US8454321B2 (en) | 2009-05-22 | 2013-06-04 | General Compression, Inc. | Methods and devices for optimizing heat transfer within a compression and/or expansion device |
US8104274B2 (en) | 2009-06-04 | 2012-01-31 | Sustainx, Inc. | Increased power in compressed-gas energy storage and recovery |
US8247915B2 (en) | 2010-03-24 | 2012-08-21 | Lightsail Energy, Inc. | Energy storage system utilizing compressed gas |
US8196395B2 (en) | 2009-06-29 | 2012-06-12 | Lightsail Energy, Inc. | Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange |
US8436489B2 (en) | 2009-06-29 | 2013-05-07 | Lightsail Energy, Inc. | Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange |
US8146354B2 (en) | 2009-06-29 | 2012-04-03 | Lightsail Energy, Inc. | Compressed air energy storage system utilizing two-phase flow to facilitate heat exchange |
WO2011056855A1 (en) | 2009-11-03 | 2011-05-12 | Sustainx, Inc. | Systems and methods for compressed-gas energy storage using coupled cylinder assemblies |
AU2010336379B2 (en) | 2009-12-24 | 2015-10-29 | General Compression Inc. | System and methods for optimizing efficiency of a hydraulically actuated system |
US8171728B2 (en) | 2010-04-08 | 2012-05-08 | Sustainx, Inc. | High-efficiency liquid heat exchange in compressed-gas energy storage systems |
US8234863B2 (en) | 2010-05-14 | 2012-08-07 | Sustainx, Inc. | Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange |
US20110204064A1 (en) | 2010-05-21 | 2011-08-25 | Lightsail Energy Inc. | Compressed gas storage unit |
US20120047884A1 (en) | 2010-08-30 | 2012-03-01 | Mcbride Troy O | High-efficiency energy-conversion based on fluid expansion and compression |
-
2010
- 2010-03-12 US US12/723,084 patent/US7963110B2/en not_active Expired - Fee Related
- 2010-03-12 WO PCT/US2010/027138 patent/WO2010105155A2/en active Application Filing
-
2011
- 2011-05-17 US US13/109,716 patent/US8234868B2/en not_active Expired - Fee Related
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4206608A (en) * | 1978-06-21 | 1980-06-10 | Bell Thomas J | Natural energy conversion, storage and electricity generation system |
BE898225A (en) * | 1983-11-16 | 1984-03-16 | Fuchs Julien | Hydropneumatic power unit - has hydraulic motor fed by pump driven by air motor from vessel connected to compressor on hydromotor shaft |
US5819635A (en) * | 1996-12-19 | 1998-10-13 | Moonen; Raymond J. | Hydraulic-pneumatic motor |
US6718761B2 (en) * | 2001-04-10 | 2004-04-13 | New World Generation Inc. | Wind powered hydroelectric power plant and method of operation thereof |
US6651545B2 (en) * | 2001-12-13 | 2003-11-25 | Caterpillar Inc | Fluid translating device |
US7000389B2 (en) * | 2002-03-27 | 2006-02-21 | Richard Laurance Lewellin | Engine for converting thermal energy to stored energy |
US20100037604A1 (en) * | 2006-07-21 | 2010-02-18 | William Hugh Salvin Rampen | Fluid power distribution and control system |
US20090317266A1 (en) * | 2006-07-27 | 2009-12-24 | William Hugh Salvin Rampen | Digital hydraulic pump/motor torque modulation system and apparatus |
US20100133903A1 (en) * | 2007-05-09 | 2010-06-03 | Alfred Rufer | Energy Storage Systems |
US20100257862A1 (en) * | 2007-10-03 | 2010-10-14 | Isentropic Limited | Energy Storage |
US7932620B2 (en) * | 2008-05-01 | 2011-04-26 | Plant Jr William R | Windmill utilizing a fluid driven pump |
Cited By (34)
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US8234868B2 (en) | 2012-08-07 |
US20100229544A1 (en) | 2010-09-16 |
US7963110B2 (en) | 2011-06-21 |
WO2010105155A2 (en) | 2010-09-16 |
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